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UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

SCHEDULE 14A

Proxy Statement Pursuant to Section 14(a) of
the Securities Exchange Act of 1934

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Interline Brands, Inc.
701 San Marco Boulevard
Jacksonville, Florida 32207
(904) 421-1400

August 1, 2012

Dear Stockholder:

        You are cordially invited to attend a special meeting of stockholders of Interline Brands, Inc., a Delaware corporation ("Interline" or the "Company"), to be held on August 29, 2012, at 10:00 a.m., local time, at the offices of the Company, located at 701 San Marco Boulevard, Jacksonville, Florida 32207.

        At the special meeting, you will be asked to (i) adopt an Agreement and Plan of Merger, dated as of May 29, 2012 (as it may be amended, the "merger agreement"), by and among Isabelle Holding Company Inc., a Delaware corporation (which corporation may be converted into a Delaware limited liability company prior to the closing of the merger (as defined herein)), an affiliate of GS Capital Partners VI L.P. and interests of which will be owned, at the closing of the transactions contemplated by the merger agreement, by one or more investment funds managed by P2 Capital Partners, LLC and certain members of Company management ("Parent"), Isabelle Acquisition Sub Inc., a Delaware corporation and a wholly owned subsidiary of Parent ("Merger Sub"), and the Company, pursuant to which Merger Sub will be merged with and into the Company (the "merger") with the Company surviving as a wholly owned subsidiary of Parent and (ii) cast an advisory (non-binding) vote to approve certain agreements or understandings, with and items of compensation that are based on or otherwise related to the merger payable to, certain Interline named executive officers under agreements with the Company (the "golden parachute" compensation).

        If the merger is completed, each share of Interline common stock, par value $0.01 per share, that you own immediately prior to the effective time of the merger, other than as provided below, will be converted into the right to receive $25.50 in cash (the "per share merger consideration"), without interest and less applicable withholding taxes. The following shares of Interline common stock will not be converted into the right to receive the per share merger consideration in connection with the merger: (a) shares of common stock owned by the Company, (b) shares of common stock owned by Parent or Merger Sub, including shares contributed to Parent by P2 Capital Master Fund I, L.P., an affiliated fund of P2 Capital Partners, LLC or (c) shares of common stock whose holders have not voted in favor of adopting the merger agreement and have demanded and perfected their appraisal rights under Section 262 of the General Corporation Law of the State of Delaware. Immediately following the completion of the merger, Parent will own all of the Company's issued and outstanding capital stock. As a result, the Company will no longer have its stock listed on the New York Stock Exchange and will no longer be required to file periodic and other reports with the Securities and Exchange Commission with respect to Interline common stock. After the merger, you will no longer have an equity interest in the Company and will not participate in any potential future earnings of the Company.

        The Company's Board of Directors has unanimously approved and authorized the merger agreement and the transactions contemplated by the merger agreement, including the merger, determined that the merger agreement is advisable and in the best interest of the Company's stockholders, and recommends that you vote "FOR" adoption of the merger agreement. In arriving at its recommendations, the Company's Board of Directors carefully considered a number of factors described in the accompanying Proxy Statement.

        The Company's Board of Directors also recommends that you vote "FOR" advisory (non-binding) approval of the "golden parachute" compensation. Adoption of the merger agreement and approval of the "golden parachute" compensation are subject to separate votes by the Company's stockholders, and approval of the "golden parachute" compensation is not a condition to completion of the merger.

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        In considering the recommendation of the Company's Board of Directors, you should be aware that some of the Company's directors and executive officers have interests in the merger that are different from, or in addition to, the interests of the Company's stockholders generally.

        If your shares are held in "street name" by your broker, bank or other nominee, your broker, bank or other nominee will be unable to vote your shares without receiving instructions from you. You should instruct your broker, bank or other nominee to vote your shares, and you should do so following the procedures provided by your broker, bank or other nominee. Failure to instruct your broker, bank or other nominee to vote your shares will have the same effect as voting against adoption of the merger agreement and approval of the advisory non-binding vote on the "golden parachute" compensation.

        If you do not hold your shares in "street name" and you complete, sign and return your proxy card without indicating how you wish to vote, your proxy will be voted in favor of adoption of the merger agreement and approval of the "golden parachute" compensation. If you fail to return your proxy card and fail to vote at the special meeting, the effect will be the same as a vote against adoption of the merger agreement and approval of the advisory non-binding vote on "golden parachute" compensation. Returning the proxy card does not deprive you of your right to attend the special meeting and vote your shares in person.

        Your proxy may be revoked at any time before it is voted by submitting a later-dated proxy to the Company by Internet, by telephone or by mail, by submitting a written revocation to the Company's corporate secretary prior to the vote at the special meeting, or by attending and voting in person at the special meeting. For shares held in "street name," you may revoke or change your vote by submitting instructions to your bank, broker or other nominee.

        Any holder of Interline common stock who does not vote in favor of the adoption of the merger agreement will have the right to seek appraisal of the fair value of their shares of Interline common stock in lieu of the per share merger consideration if the merger is completed, but only if they submit a written demand for appraisal of their shares before the taking of the vote on the merger agreement at the special meeting and they comply with all requirements of Section 262 of the General Corporation Law of the State of Delaware for exercising appraisal rights, which are summarized in the accompanying Proxy Statement.

        The merger cannot be completed unless the holders of a majority of the outstanding shares of Interline common stock adopt the merger agreement. Whether or not you plan to attend the special meeting, please complete, sign and return the enclosed proxy card or submit your proxy by following the instructions on the proxy card.

        Thank you for your continued support.

		Sincerely,
		Michael J. Grebe Chairman of the Board and Chief Executive Officer

        Neither the U.S. Securities and Exchange Commission nor any state securities commission has approved or disapproved the merger, passed upon the merits or fairness of the merger agreement or the transactions contemplated thereby, including the proposed merger, or passed upon the adequacy or accuracy of the information contained in this document or the accompanying Proxy Statement. Any representation to the contrary is a criminal offense.

        The accompanying Proxy Statement is dated August 1, 2012 and is first being mailed to the Company's stockholders on or about August 1, 2012.

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NOTICE OF SPECIAL MEETING OF STOCKHOLDERS
TO BE HELD ON AUGUST 29, 2012

INTERLINE BRANDS, INC.

To the Stockholders of Interline Brands, Inc.:

        Notice is hereby given that a special meeting of stockholders of Interline Brands, Inc., a Delaware corporation ("Interline" or the "Company"), will be held on August 29, 2012, at 10:00 a.m., local time, at the offices of the Company, located at 701 San Marco Boulevard, Jacksonville, Florida 32207, for the following purposes:

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To consider and vote on a proposal to adopt the Agreement and Plan of Merger, dated as of May 29, 2012 (as it may be amended, the "merger agreement"), by and among Isabelle Holding Company Inc., a Delaware corporation (which corporation may be converted into a Delaware limited liability company prior to the closing of the merger (as defined herein)), an affiliate of GS Capital Partners VI L.P. and interests of which will be owned, at the closing of the transactions contemplated by the merger agreement, by one or more investment funds managed by P2 Capital Partners, LLC and certain members of Company management ("Parent"), Isabelle Acquisition Sub Inc., a Delaware corporation and a wholly owned subsidiary of Parent ("Merger Sub"), and the Company, providing for the merger of Merger Sub with and into the Company (the "merger"), with the Company surviving the merger as a wholly owned subsidiary of Parent;



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To consider and cast an advisory (non-binding) vote on a proposal to approve certain agreements or understandings with, and items of compensation payable to, the Company's named executive officers that are based on or otherwise related to the merger (the "golden parachute" compensation);



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To consider and vote upon a proposal to adjourn the special meeting, if necessary or appropriate, to solicit additional proxies if there are insufficient votes at the time of the special meeting to adopt the merger agreement; and



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To consider and vote upon any other matters that properly come before the special meeting or any adjournment or postponement thereof.

        Only holders of record of Interline common stock, par value $0.01 per share, at the close of business on July 26, 2012, the record date of the special meeting, are entitled to notice of, and to vote at, the special meeting or any adjournments or postponements of the special meeting.

        The merger agreement, the merger and the "golden parachute" compensation arrangements are more fully described in the accompanying Proxy Statement, which the Company urges you to read carefully and in its entirety. A copy of the merger agreement is attached as Appendix A to the accompanying Proxy Statement, which the Company also urges you to read carefully and in its entirety.

        The merger cannot be completed unless the holders of a majority of the outstanding shares of Interline common stock approve the merger agreement. The approval of the "golden parachute" compensation is advisory (non-binding) and is not a condition to completion of the merger. Whether or not you plan to attend the special meeting, please complete, sign and return the enclosed proxy card or submit your proxy by Internet, by telephone or by mail following the instructions on the proxy card.

        The affirmative vote of the holders of a majority of the shares of Interline common stock outstanding and entitled to vote is necessary to adopt the merger agreement.

        The Company's Board of Directors has unanimously approved and authorized the merger agreement, and recommends that you vote "FOR" adoption of the merger agreement. The Company's Board of Directors recommends that you vote "FOR" approval, on an advisory (non-binding) basis, of the "golden parachute" compensation payable to the Company's named executive officers in connection with the merger.

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        Under the Delaware General Corporation Law, the Company's stockholders may exercise appraisal rights in connection with the merger. Stockholders who do not vote in favor of the proposal to adopt the merger agreement and who comply with all of the other necessary procedural requirements under the Delaware General Corporation Law will have the right to dissent from the merger and to seek appraisal of the fair value of their Interline shares in lieu of receiving the per share merger consideration, as determined by the Delaware Court of Chancery. For a description of appraisal rights and the procedures to be followed to assert them, stockholders should review the provisions of Section 262 of the General Corporation Law of the State of Delaware, a copy of which is included as Appendix B to the accompanying Proxy Statement.

        The affirmative vote of the majority of the shares present in person or represented by proxy and entitled to vote on the proposal is required for the approval of the advisory (non-binding) proposal on "golden parachute" compensation.

        The Company urges you to read the Proxy Statement and merger agreement carefully and in their entirety.

        If you have questions about the merger agreement or the merger, including the procedures for voting your shares, you should contact Michael Agliata via telephone at (904) 421-1471 or via email at Michael.Agliata@interlinebrands.com. You may also call the Company's proxy solicitor Georgeson Inc., toll-free at 1-888-206-5896.

		BY ORDER OF THE BOARD OF DIRECTORS
		Michael Agliata Vice President, General Counsel and Secretary

August 1, 2012

        Please do not send your Interline common stock certificates to the Company at this time. If the merger is completed, you will be sent instructions regarding the surrender of your stock certificates.

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INTERLINE BRANDS, INC.
701 San Marco Boulevard
Jacksonville, Florida 32207

PROXY STATEMENT

        This Proxy Statement contains information related to a special meeting of stockholders of Interline Brands, Inc. to be held on August 29, 2012, at 10:00 a.m., local time, at the offices of the Company, located at 701 San Marco Boulevard, Jacksonville, Florida 32207, and at any adjournments or postponements thereof. The Company is furnishing this Proxy Statement to the Company's stockholders as part of the solicitation of proxies by the Company's Board of Directors for use at the special meeting. At the special meeting you will be asked to, among other things, consider and vote on the adoption of the merger agreement. This Proxy Statement is first being mailed to stockholders on or about August 1, 2012.

SUMMARY TERM SHEET

        This following summary term sheet highlights selected information contained in this Proxy Statement and may not contain all of the information that is important to you. The Company urges you to read this entire Proxy Statement carefully, including the appendices, before voting. The Company has included section references to direct you to a more complete description of the topics described in this summary term sheet. You may obtain the information incorporated by reference into this Proxy Statement without charge by following the instructions in "Where Stockholders Can Find More Information" beginning on page 103. Unless the context requires otherwise, references in this Proxy Statement to the "Company" or "Interline" refer to Interline Brands, Inc., a Delaware corporation, references to "Parent" refer to Isabelle Holding Company Inc., a Delaware corporation (which corporation may be converted into a Delaware limited liability company prior to the closing of the merger (as defined herein)), and references to "Merger Sub" refer to Isabelle Acquisition Sub Inc., a Delaware corporation.

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Purpose of Stockholders' Vote.  You are being asked to:



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consider and vote upon a proposal (the "merger proposal") to adopt the Agreement and Plan of Merger, dated as of May 29, 2012, by and among Parent, Merger Sub and the Company, as it may be amended from time to time, which is referred to in this Proxy Statement as it may so be amended, as the "merger agreement". A copy of the merger agreement is attached hereto as Appendix A. Pursuant to the merger agreement, Merger Sub will be merged with and into the Company (the "merger"), and the Company will continue as the surviving corporation and become a wholly owned subsidiary of Parent. If the merger is completed, each issued and outstanding share of Interline common stock, other than as provided below, will be converted into the right to receive $25.50 in cash, without interest and less applicable withholding taxes. The following shares of Interline common stock will not be converted into the right to receive the per share merger consideration in connection with the merger: (a) shares of common stock owned by the Company, (b) shares of common stock owned by Parent or Merger Sub, including shares contributed to Parent by P2 Capital Master Fund I, L.P., an affiliated fund of P2 Capital Partners, LLC (the "P2 Fund") and certain members of the Company management or (c) shares of common stock whose holders have not voted in favor of adopting the merger agreement and have demanded and perfected their appraisal rights under Section 262 of the General Corporation Law of the State of Delaware (the "DGCL"). See "The Special Meeting" beginning on page 22 and "The Merger (Proposal 1)" beginning on page 26; and



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approve on an advisory (non-binding) basis certain agreements and other items of compensation tied to or based on the merger payable to the Company's named executive

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officers under arrangements with the Company (which is referred to in this Proxy Statement as the "golden parachute" compensation). See "Advisory Vote on Golden Parachute Compensation (Proposal 2)" beginning on page 96.

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Required Vote of the Company's Stockholders.



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Under the DGCL, the affirmative vote of the holders of a majority of the shares of Interline common stock outstanding and entitled to vote is necessary to approve the merger agreement. Abstentions and broker non-votes will have the same effect as a vote against adoption of the merger agreement.



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The affirmative vote of the majority of the shares present in person or represented by proxy and entitled to vote on the proposal is required for the approval of the advisory (non-binding) proposal on the "golden parachute" compensation. The vote to approve the "golden parachute" compensation is advisory only and will not be binding on the Company or Parent and is not a condition to completion of the merger. If the merger agreement is adopted by the stockholders and completed, the "golden parachute" compensation may be paid to the Company's named executive officers even if stockholders fail to approve the golden parachute compensation. Abstentions are treated as a vote against the proposal to approve the "golden parachute" compensation if your shares are otherwise present in person or otherwise represented in proxy at the special meeting. However, broker non-votes (or other failures to vote) will have no effect on the proposal to approve the "golden parachute" compensation.



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The approval of the proposal to adjourn the special meeting if there are not sufficient votes to adopt the merger proposal requires the affirmative vote of stockholders holding a majority of the shares present in person or by proxy at the special meeting and entitled to vote thereon. See "The Special Meeting—Record Date; Stockholders Entitled to Vote; Quorum; Voting Information" beginning on page 23 and "Advisory Vote on Golden Parachute Compensation (Proposal 2)" beginning on page 96.



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Parties Involved in the Proposed Transaction.  The Company, a Delaware corporation headquartered in Jacksonville, Florida, is a leading national distributer and direct marketer of maintenance, repair and operations products. Parent is a Delaware corporation (which corporation may be converted into a Delaware limited liability company prior to the consummation of the merger) affiliated with GS Capital Partners VI L.P. and interests of which will be owned, at the closing of the transactions contemplated by the merger agreement, by one or more investment funds managed by P2 Capital Partners, LLC and certain members of Company management. Merger Sub is a Delaware corporation and a wholly owned subsidiary of Parent. Both Parent and Merger Sub were formed for the sole purpose of entering into the merger agreement and consummating the transactions contemplated by the merger agreement. See "The Companies" beginning on page 19.



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Special Meeting.  The stockholders' vote will take place at a special meeting to be held on August 29, 2012, at 10:00 a.m., local time, at the offices of the Company, located at 701 San Marco Boulevard, Jacksonville, Florida 32207. See "The Special Meeting" beginning on page 22.



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Conditions to the Merger.  The completion of the merger is subject to the satisfaction or waiver of conditions, which are described in "The Merger Agreement—Conditions to the Completion of the Merger" beginning on page 89. These conditions include, among others:



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the adoption of the merger agreement by the holders of a majority of the outstanding shares of Interline common stock;

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the expiration or termination of the regulatory waiting period under the Hart-Scott-Rodino Antitrust Improvements Act of 1976 (the "HSR Act"), which waiting period terminated on June 20, 2012;



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the absence of any order or law of any governmental entity that restrains, enjoins or otherwise prohibits the consummation of the merger or the other material transactions contemplated by the merger agreement;



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the absence of a material adverse effect on the Company;



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the delivery of a certificate of the chief financial officer of the Company to Parent certifying that the unrestricted cash as of the closing date of the Company and its domestic subsidiaries available to be lawfully dividended to the Company by its subsidiaries in compliance with the Existing Indenture (less the principal amount drawn under the Company's existing ABL credit facility as of the closing date) is not less than $50 million;



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the Company's, Parent's and Merger Sub's performance in all material respects of their agreements and covenants in the merger agreement (subject to certain exceptions); and



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the accuracy of the representations and warranties of the Company (subject in certain cases to certain materiality, knowledge and other qualifications), and the accuracy of the representation and warranty with regard to the ability as of May 29, 2012 of Interline Brands, Inc., a New Jersey corporation and a direct subsidiary of the Company ("Interline New Jersey"), to make restricted payments in compliance with the indenture governing the outstanding 7.00% senior subordinated notes due 2018 issued by Interline New Jersey (the "Existing Notes") in an amount of not less than $200 million.



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Marketing Period.  The merger agreement provides that the closing of the merger is to take place on the third business day after the day on which the conditions to closing (other than those conditions that by their terms are to be satisfied by actions taken at the closing) are satisfied or waived. However, if the marketing period has not ended at such time, then the marketing period will commence on September 5, 2012 and end on September 25, 2012 and the closing may not occur earlier than September 28, 2012, unless Parent agrees to an earlier closing. Notwithstanding the requirement in the immediately preceding sentence, Parent has advised the Company that Parent expects the merger to close in early to mid September if all of the conditions to closing are satisfied or waived by that time, although there is no assurance that the merger will close prior to September 28, 2012, if at all. For additional information on the marketing period, see "The Merger Agreement—Closing and Effective Time of The Merger; Marketing Period" beginning on page 68.



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Regulatory Approvals.  The merger cannot be completed until the Company and Parent each (i) file a notification and report form under the HSR Act and (ii) the applicable waiting periods have expired or been terminated. Early termination of the waiting period under the HSR Act with respect to the merger was granted on June 20, 2012. See "The Merger (Proposal 1)—Regulatory Approvals."



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Record Date.  You are entitled to vote at the special meeting if you owned shares of Interline common stock at the close of business on July 26, 2012, which is the record date for the special meeting. On the record date, 31,930,798 shares of Interline common stock were outstanding and entitled to vote at the special meeting. See "The Special Meeting—Record Date; Stockholders Entitled to Vote; Quorum; Voting Information" beginning on page 23.



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Voting Information.  You will have one vote for each share of Interline common stock that you owned at the close of business on the record date. If your shares are held in "street name" by a broker, you will need to provide your broker with instructions on how to vote your shares. Before voting your shares of Interline common stock, you should read this Proxy Statement in its entirety, including its

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appendices, and carefully consider how the merger affects you. Then, submit your completed, dated and signed proxy by Internet, by telephone or by mail, as soon as possible so that your shares can be voted at the special meeting. For more information on how to vote your shares, please refer to "The Special Meeting—Record Date; Stockholders Entitled to Vote; Quorum; Voting Information" beginning on page 23.

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Board Recommendation.  The Company's Board of Directors, after careful consideration, has unanimously approved and authorized the merger agreement and the transactions contemplated by the merger agreement, including the merger, determined that the merger agreement is advisable and in the best interests of the stockholders of the Company, and recommends that you vote "FOR" adoption of the merger agreement. The Company's Board of Directors also recommends that you vote "FOR" approval of the "golden parachute" compensation. See "The Merger (Proposal 1)—Recommendation of the Company's Board of Directors" beginning on page 34 and see "Advisory Vote on Golden Parachute Compensation (Proposal 2)" beginning on page 96.



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Opinion of Barclays.  On May 28, 2012, in connection with the merger, the Company's financial advisor, Barclays Capital Inc. ("Barclays"), rendered its oral opinion, which opinion was subsequently confirmed in a written opinion dated May 29, 2012, to the Company's Board of Directors to the effect that, as of that date and based upon and subject to the qualifications, limitations and assumptions stated in its written opinion, the per share merger consideration of $25.50 to be offered to the stockholders of the Company in the merger was fair, from a financial point of view, to such stockholders (other than P2 Capital Partners, LLC and its affiliated funds).

The full text of the written opinion, dated May 29, 2012, which sets forth, among other things, the assumptions made, procedures followed, factors considered and limitations upon the review undertaken by Barclays in rendering its opinion, is attached as Appendix C to this Proxy Statement. The Company encourages you to read the opinion carefully in its entirety. Barclays' opinion is addressed to the Company's Board of Directors, addresses only the fairness, from a financial point of view, of the per share merger consideration to be offered to the stockholders of Interline (other than P2 Capital Partners, LLC and its affiliated funds) and does not constitute a recommendation to any stockholder of Interline as to how such stockholder should vote with respect to the merger or any other matter.

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Financing of the Merger.  Parent has obtained equity commitments from GS Capital Partners VI Fund, L.P. ("GS Fund VI"), GS Capital Partners VI Parallel, L.P., GS Capital Partners VI Offshore Fund, L.P. and GS Capital Partners VI GmbH & Co (collectively, the "GS Funds") and the P2 Fund and Parent has advised the Company that Merger Sub has obtained the debt financing commitments from Goldman Sachs Lending Partners LLC, Merrill Lynch, Pierce, Fenner & Smith Incorporated and Bank of America, N.A. for the transactions contemplated by the merger agreement, the aggregate proceeds of which (together with cash on hand of the Company at closing) are expected to be sufficient for Parent and Merger Sub to pay the aggregate merger consideration, the amounts payable with respect to the Company's stock options and the Company's restricted share units, and the related fees and expenses of the transactions contemplated by the merger agreement. The consummation of the merger is not subject to any financing conditions (although funding of the equity and debt financing is subject to the satisfaction of the conditions set forth in the commitment letters under which the financing will be provided). See "The Merger (Proposal 1)—Merger Financing" beginning on page 51.



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Limited Guarantees.  In connection with the merger agreement, GS Fund VI and the P2 Fund have each executed a limited guarantee in favor of the Company to guarantee, subject to the limitations described therein, 100% in the case of GS Fund VI and 8.05% in the case of the P2 Fund, of the payment of certain payment obligations that may be owed by Parent and/or Merger Sub pursuant to the merger agreement, including certain indemnification and reimbursement obligations under the

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merger agreement, the payment of any reverse termination fee that may become payable by Parent and Merger Sub following a termination of the merger agreement by the Company in specified circumstances, and all costs and expenses (including attorney's fees and expenses) reasonably incurred by the Company in connection with the enforcement of the limited guarantee or the exercise of specific performance under the merger agreement. The guarantees are subject to an overall cap of $68.4 million plus the amount of the reimbursement and indemnification obligations under the merger agreement and any costs and expenses reasonably incurred by the Company in connection with the enforcement of the limited guarantee or the exercise of specific performance under the merger agreement. The Company is contractually entitled to require such affiliates to perform under the guarantees. See "The Merger (Proposal 1)—Merger Financing" beginning on page 51.

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Interests of the Company's Directors and Executive Officers in the Merger.  No stockholder is entitled to receive any special merger consideration. However, in considering the recommendation of the Company's Board of Directors, you should be aware that some of the Company's executive officers and directors have interests in the merger that may be different from your interests as a stockholder and that may present actual or potential conflicts of interest. Additionally, the Company's chief executive officer has agreed to reinvest $6.7 million in Parent at the time of the merger, and it is anticipated that other members of the Company's senior management will reinvest between 30% and 50% of their after-tax proceeds from the merger attributable to each component of their existing equity, on terms to be agreed upon between management and Parent, a portion of which, in each case, may be satisfied through an exchange of shares and/or options (which in the case of options will be based on the intrinsic value of the exchanged options on the date of closing of the merger) in the Company for shares and/or options in Parent. These interests are discussed in "The Merger (Proposal 1)—Interests of the Company's Directors and Executive Officers in the Merger" beginning on page 54 and "Advisory Vote on Golden Parachute Compensation (Proposal 2)" beginning on page 96.



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Material U.S. Federal Income Tax Consequences of the Merger.  The merger will be a taxable event for United States ("U.S.") federal income tax purposes. Each U.S. holder (as defined in this Proxy Statement) will recognize a taxable gain or loss equal to the difference between the consideration received (prior to reduction for any applicable withholding taxes) in the merger and the U.S. holder's adjusted tax basis in the shares of Interline common stock surrendered. See "The Merger (Proposal 1)—Material U.S. Federal Income Tax Consequences" beginning on page 62 for a discussion of material U.S. federal income tax consequences of the merger to certain U.S. holders. The tax consequences of the merger to you will depend on the facts of your own situation. You should consult your tax advisor for a full understanding of the tax consequences of the merger to you.



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Treatment of Outstanding Options, Restricted Share Units and Restricted Stock.  Unless otherwise agreed upon between Parent and any such stock option holder, immediately prior to the effective time of the merger, each stock option issued under the Company's equity compensation plans or programs, whether or not then exercisable or vested, will be cancelled and converted into the right to receive an amount in cash equal to, without interest and less applicable withholding taxes, the product of (i) the excess, if any, of $25.50 (the per share merger consideration) over the per share exercise price of the applicable stock option and (ii) the aggregate number of shares of common stock that may be acquired upon exercise of such stock option immediately prior to the effective time of the merger. Also at the effective time of the merger, unless otherwise agreed upon between Parent and any such holder, each restricted share unit granted under the Company's equity compensation plans or programs will vest (to the extent not already vested) in accordance with its terms. Further, in connection with the action approving the merger and the merger agreement, the Company's Board of Directors authorized the accelerated vesting of the performance conditions applicable to restricted share units outstanding immediately prior to the consummation of the

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merger. Under the merger agreement, with respect to any portion of a restricted share unit award that vests on achievement of performance conditions, the number of shares of Interline common stock subject to such award will be equal to the maximum amount of such award. Accordingly, unless otherwise agreed upon between Parent and any such holder, all restricted share units will vest at the maximum amount of such award as of immediately prior to the consummation of the merger. At the effective time of the merger, unless otherwise agreed upon between Parent and any such holder, each vested restricted share unit will be converted into the right to receive an amount in cash equal to $25.50 (the per share merger consideration) per share of Interline common stock underlying such restricted share unit, without interest and less applicable withholding taxes. Also at the effective time of the merger, unless otherwise agreed upon between Parent and any such holder, each share of restricted stock granted under the Company's equity compensation plans or programs will vest (to the extent not already vested) in accordance with its terms and each vested share of restricted stock will be converted into the right to receive an amount in cash equal to $25.50 (the per share merger consideration) per share of Interline common stock underlying such share of restricted stock, without interest and less applicable withholding taxes. As of the date of this Proxy Statement, there are no shares of restricted stock outstanding.

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Appraisal Rights.  Stockholders who oppose the merger may exercise their right to seek appraisal of the fair value of their shares of Interline common stock as determined by the Court of Chancery of the State of Delaware if the merger is completed, but only if they do not vote in favor of adopting the merger agreement and otherwise comply with the procedures of Section 262 of the DGCL, which is the appraisal rights statute applicable to Delaware corporations. A copy of Section 262 of the DGCL is included as Appendix B to this Proxy Statement and the procedures are summarized in this Proxy Statement. See "The Merger (Proposal 1)—Appraisal Rights" beginning on page 58 and Appendix B to this Proxy Statement. This appraisal amount could be more than, the same as or less than the $25.50 per share merger consideration. Your failure to follow exactly the procedures specified under DGCL will result in the loss of your appraisal rights.



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Anticipated Closing of the Merger.  The merger will be completed after all of the conditions to the merger, as detailed above, are satisfied or waived and the marketing period has ended. The Company currently expects the merger to be completed in early to mid September 2012, although the Company cannot assure completion by any particular date, if at all. The Company will issue a press release once the merger has been completed. See "The Merger Agreement—Conditions to the Completion of the Merger" beginning on page 89.



•

Solicitations of Other Offers; "Go-Shop Period".  Following the execution of the merger agreement and continuing until 11:59 p.m. (New York City time) on June 28, 2012 (the "go-shop period"), the Company and its representatives were, subject to certain limitations specified in the merger agreement, permitted to initiate, solicit and encourage alternative acquisition proposals from third parties, including by way of providing non-public information, and enter into, engage in and maintain discussions or negotiations with third parties with respect to alternative acquisition proposals, or inquiries, proposals or offers or other efforts or attempts that could lead to an alternative acquisition proposal. The Company and its representatives were permitted to continue to engage in the activities described in the previous sentence for an additional fifteen days after the end of the go-shop period (and subject to further extension in certain circumstances) (the date such period expires, the "cut-off date") with respect to certain third parties that made alternative acquisition proposals during the go-shop period that the Company's Board of Directors determined were bona fide and were or would reasonably be expected to result in a superior proposal. Barclays, on behalf of the Company, contacted 54 potential bidders during the go-shop period. However, the Company did not receive any alternative acquisition proposals during such period. See "The Merger Agreement—Covenants of the Company—Solicitation of Acquisition Proposals; Fiduciary

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Out" beginning on page 79 and "The Merger Agreement—Effect of Termination; Fees and Expenses" beginning on page 92.

•

No-Shop Provisions after "Go-Shop Period".  Except as described in the previous bullet, starting at 12:00 a.m. on June 29, 2012, the Company became subject to customary "no-shop" provisions on its ability to solicit alternative acquisition proposals from third parties and to provide information to and enter into, engage in and maintain discussions or negotiations with third parties regarding alternative acquisition proposals. However, prior to receipt of the Stockholder Approval, the no-shop provision is subject to a "fiduciary out" provision that allows the Company to provide information and participate in discussions with respect to an unsolicited written acquisition proposal (or a proposal which was solicited during the go-shop period) that the Company's Board of Directors has determined in good faith constitutes or would reasonably be expected to lead to a superior proposal and, subject to compliance with the terms of the merger agreement (including providing Parent and Merger Sub with prior notice and allowing Parent matching rights), to change its recommendation due to an intervening event or to approve, recommend or declare advisable, and authorize the Company to enter into an acquisition agreement with respect to a superior proposal. See "The Merger Agreement—Covenants of the Company—Solicitation of Acquisition Proposals; Fiduciary Out" beginning on page 79 and "The Merger Agreement—Effect of Termination; Fees and Expenses" beginning on page 92.



•

Termination.  The merger agreement may be terminated before the completion of the merger in certain circumstances. See "The Merger Agreement—Termination" beginning on page 91.



•

Termination Fees.  The merger agreement contains certain termination rights for both the Company and Parent. The merger agreement provides that, upon termination under specified circumstances, the Company would be required to pay Parent, Goldman, Sachs & Co., and P2 Capital Partners, LLC, in the aggregate, a termination fee in an amount equal to $29.9 million plus reimbursable expenses up to a maximum of $5 million; however, if the termination in any such circumstances is in connection with a superior proposal arising during the go-shop period and entered into prior to the cut-off date, the Company would be required to pay Parent a termination fee equal to $13.9 million plus reimbursable expenses up to a maximum of $5 million. The Merger Agreement also provides that Parent will be required to pay the Company a reverse termination fee equal to $51.3 million upon termination under certain specified circumstances, and a reverse termination fee of $68.4 million in the event of termination under such circumstances if Parent has committed a willful and material breach of any of its representations, warranties, covenants or agreements under the merger agreement, other than a willful and material breach arising solely by reason of Parent and Merger Sub failing to consummate the merger if the debt financing is not available pursuant to its terms. In addition, subject to certain limitations, either party may terminate the merger agreement if the merger is not consummated by November 29, 2012. See "The Merger Agreement—Effect of Termination; Fees and Expenses" beginning on page 92.



•

Specific Performance.  Under certain circumstances, a party may seek specific performance to require the other party to complete the merger. Each party will be entitled to specifically enforce the other party's obligations to comply with its general covenants under the merger agreement. Additionally, the Company is contractually entitled to cause Parent to require the GS Funds and the P2 Fund to specifically perform the obligation to fund the equity commitment to Parent only if (i) all conditions to the closing of the merger (other than those conditions that by their nature are to be satisfied at closing or result from a material breach by Parent or Merger Sub) have been satisfied, (ii) the third business day immediately following the final day of the marketing period has occurred, (iii) the debt financing has been funded or will be funded at the closing if the equity financing is funded at the closing of the merger, (iv) Parent and Merger Sub fail to complete the closing as required by the merger agreement, and (v) the Company has confirmed in a written notice to Parent that if specific performance is granted and the equity and debt financing are

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funded, then the closing of the merger will occur. Additionally, the obligation of the GS Funds and the P2 Fund to fund the equity commitment is subject to the conditions set forth in the equity commitment letter. See "The Merger Financing—Equity Financing" beginning on page 51. If a termination fee or a reverse termination fee is due and payable to a party, such party is not entitled to require the other party to complete the merger. See "The Merger Agreement—Effect of Termination; Fees and Expenses" beginning on page 92 and See "The Merger (Proposal 1)—Merger Financing" beginning on page 51.

•

Additional Information.  You can find more information about the Company in the periodic reports and other information the Company files with the Securities and Exchange Commission (the "SEC"). This information is available at the SEC's public reference facilities and at the website maintained by the SEC at www.sec.gov and on the Company's website at www.interlinebrands.com. For a more detailed description of the additional information available, see "Where Stockholders Can Find More Information" beginning on page 103.

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QUESTIONS AND ANSWERS ABOUT THE MERGER AND THE
SPECIAL MEETING

        The following questions and answers, which are for your convenience only, briefly address some commonly asked questions about the merger and are qualified in their entirety by the more detailed information contained elsewhere in this Proxy Statement. These questions and answers may not address all questions that may be important to you as a stockholder of Interline. You should still carefully read this entire Proxy Statement, including the attached appendices.

Q:

Why am I receiving these materials?

A:

You are receiving this Proxy Statement and proxy card because you own shares of Interline common stock. The Company's Board of Directors is providing these proxy materials to give you information to determine how to vote in connection with the special meeting of the Company's stockholders.

Q:

When and where is the special meeting?

A:

The special meeting will be held at 10:00 a.m. local time on August 29, 2012 at the offices of the Company, located at 701 San Marco Boulevard, Jacksonville, Florida 32207.

Q:

Upon what am I being asked to vote on at the special meeting?

A:

You are being asked to consider and vote upon the following proposals:

1.

to consider and vote upon the adoption of the merger agreement, pursuant to which Merger Sub will merge with and into the Company and the Company will continue as the surviving corporation and become a wholly owned subsidiary of Parent;

2.

to consider and cast an advisory (non-binding) vote to approve the "golden parachute" compensation payable to the Company's named executive officers in connection with the merger;

3.

to consider and vote upon a proposal to approve the adjournment or postponement of the special meeting, if necessary or appropriate, to solicit additional proxies if there are insufficient votes at the time of the special meeting to adopt the merger agreement; and

4.

to consider and vote upon any other matters that properly come before the special meeting or any adjournment or postponement thereof.

Q:

Why is the merger being proposed?

A:

The Company's purpose in proposing the merger is to enable stockholders to receive, upon completion of the merger, $25.50 per share in cash, without interest and less applicable withholding taxes. After careful consideration, the Company's Board of Directors has unanimously (i) approved and declared advisable the merger agreement, the merger and the transactions contemplated by the merger agreement, (ii) declared that it is in the best interests of the stockholders of the Company that the Company enter into the merger agreement and consummate the merger on the terms and subject to the conditions set forth in the merger agreement, (iii) directed that the adoption of the merger agreement be submitted to a vote at a meeting of the stockholders of the Company and (iv) recommended that the stockholders of the Company vote "FOR" the adoption of the merger agreement. For a more detailed discussion of the conclusions, determinations and reasons of the Company's Board of Directors for recommending that the Company undertake the merger on the terms of the merger agreement, see "The Merger (Proposal 1)—Recommendation of the Company's Board of Directors," beginning on page 34.

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Q:

What will happen in the merger?

A:

In the merger, Merger Sub will be merged with and into the Company and the Company will continue as the surviving corporation and become a wholly owned subsidiary of Parent. As a result of the merger, Interline common stock will no longer be publicly traded, and you will no longer have any interest in the Company's future earnings or growth. In addition, Interline common stock will be delisted from the New York Stock Exchange and deregistered under the Securities Exchange Act of 1934, as amended, and the Company will no longer be required file periodic reports with the SEC with respect to Interline common stock in each case in accordance with applicable law, rules and regulations.

Q:

What will I receive in the merger?

A:

If the merger is completed, you will be entitled to receive $25.50 in cash, without interest and less any applicable withholding taxes, for each share of Interline common stock that you own immediately prior to the effective time of the merger. For example, if you own 100 shares of Interline common stock, you will receive $2,550.00 in cash in exchange for your shares of Interline common stock, without giving effect to any applicable withholding taxes. This does not apply to (a) shares held by any of the Company's stockholders who are entitled to and who properly exercise, and do not properly withdraw, their appraisal rights under the DGCL, (b) shares held by the Company, or (c) shares held by Parent or Merger Sub. You will not own any shares of the capital stock in the surviving corporation.

Q:

How does the per share merger consideration compare to the market price of Interline common stock prior to announcement of the merger?

A:

The $25.50 per share merger consideration represents a premium of approximately 42% relative to the Company's closing stock price on May 25, 2012, the last trading day before the announcement of the transaction, and 31% relative to the Company's trailing 30-day average closing stock price for the period ended on May 25, 2012.

Q:

What is the recommendation of the Company's Board of Directors?

A:

Based on the factors described in "The Merger (Proposal 1)—Recommendation of the Company's Board of Directors," the Company's Board of Directors has unanimously approved the merger agreement and recommends that you vote "FOR" the merger agreement. In the opinion of the Company's Board of Directors, the merger agreement and the terms and conditions of the merger are in the best interests of the Company and its stockholders. The Company's Board of Directors also recommends that you vote "FOR" approval of the "golden parachute" compensation. See "The Merger (Proposal 1)—Recommendation of the Company's Board of Directors" beginning on page 34 and "Advisory Vote on Golden Parachute Compensation (Proposal 2)" beginning on page 96.

Q:

Who will own the Company after the merger?

A:

Immediately following the merger, the Company will be a wholly owned subsidiary of Parent, an affiliate of the GS Funds, the P2 Fund and certain other investment funds managed by the P2 Capital Partners, LLC and certain members of Company management.

Q:

What are the consequences of the merger to present members of management and the Company's Board of Directors?

A:

Shares of common stock owned by members of management and the Company's Board of Directors will be treated the same as shares held by other stockholders. Except as may otherwise be agreed to between Parent and a particular award holder, options and restricted share units owned by members of management and the Company's Board of Directors will be treated the same as outstanding

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options and restricted share units held by other employees. See "Treatment of Outstanding Options and Restricted Share Units" in the Summary Term Sheet section above. For other payments and benefits to the Company's named executive officers that are tied to or based on the merger, see "Advisory Vote on Golden Parachute Compensation (Proposal 2)" beginning on page 96.

In connection with the closing of the merger, the Company's Chief Executive Officer has agreed to reinvest $6.7 million in Parent at the time of the merger, and other members of management are expected to reinvest between 30% and 50% of their after-tax proceeds from the merger attributable to each component of their existing equity, a portion of which, in each case, may be satisfied through an exchange of shares and/or options (which in the case of options will be based on the intrinsic value of the exchanged options on the date of closing of the merger) in the Company for shares and/or options in Parent.

Q:

Is the merger subject to the satisfaction of any conditions?

A:

Yes. The completion of the merger is subject to the satisfaction or waiver of the conditions described in "The Merger Agreement—Conditions to the Completion of the Merger" beginning on page 89. These conditions include, among others:

•

the adoption of the merger agreement by stockholders holding a majority of the outstanding shares of Interline common stock;

•

the expiration or termination of the regulatory waiting periods under the HSR Act;

•

the absence of any order or law of any governmental entity that restrains, enjoins or otherwise prohibits the consummation of the merger or the other material transactions contemplated by the merger agreement;

•

the absence of a material adverse effect on the Company;

•

the delivery of a certificate of the chief financial officer of the Company to Parent certifying that the unrestricted cash as of the closing date of the Company and its domestic subsidiaries available to be lawfully dividended to the Company by its subsidiaries in compliance with the indenture governing the Company's Existing Notes (less the principal amount drawn under the Company's existing ABL credit facility as of the closing date) is not less than $50 million;

•

the Company's, Parent's and Merger Sub's performance in all material respects of their agreements and covenants in the merger agreement (subject to certain exceptions); and

•

the accuracy of the representations and warranties of the Company (subject in certain cases to certain materiality, knowledge and other qualifications), and the accuracy of the representation and warranty with regard to the ability as of May 29, 2012 of Interline New Jersey to make restricted payments in compliance with the indenture governing the Existing Notes in an amount of not less than $200 million.

Q:

Who can attend and vote at the special meeting?

A:

All holders of Interline common stock at the close of business on July 26, 2012, the record date for the special meeting, will be entitled to vote (in person or by proxy) on the merger agreement at the special meeting or any adjournments or postponements of the special meeting.

Q:

What vote is required to approve the merger agreement?

A:

The merger agreement will be adopted by the affirmative vote of a majority of the shares of Interline common stock outstanding on the record date. Because the required vote is based on the number of shares of Interline common stock outstanding rather than on the number of votes cast, failure to vote

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your shares (including as a result of broker non-votes) and abstentions will have the same effect as voting against the adoption of the merger agreement. The Company urges you to either complete, execute and return the enclosed proxy card or submit your proxy or voting instructions by Internet, by telephone or by mail to assure the representation of your shares of Interline common stock at the special meeting. A "broker non-vote" occurs when a broker does not have discretion to vote on the matter and has not received instructions from the beneficial holder as to how such holder's shares are to be voted on the matter.

Q:

Have any stockholders already agreed to approve the merger?

A:

In connection with the merger agreement, the P2 Fund, which, together with P2 Capital Master Fund VI, L.P., collectively owns as of May 25, 2012, 7.9% of the outstanding shares of the Company, has entered into an investor support agreement with Parent, dated as of May 29, 2012, pursuant to which the P2 Fund has agreed to vote, and to use its best efforts to cause P2 Capital Master Fund VI, L.P. to vote, its shares of Interline common stock in favor of the adoption of the merger agreement.

Other than the P2 Fund, none of the Company's stockholders have entered into a voting agreement with the Company to vote their shares of Interline common stock in favor of the adoption of the merger agreement.

Q:

Why am I being asked to cast an advisory (non-binding) vote to approve "golden parachute" compensation payable to certain of the Company's named executive officers in connection with the merger?

A:

The SEC rules require the Company to seek an advisory (non-binding) vote with respect to certain payments that will be made to the Company's named executive officers in connection with the merger.

Q:

What is the "golden parachute" compensation?

A:

The "golden parachute" compensation is certain compensation that is tied to or based on the merger and payable to certain of the Company's named executive officers. See "Advisory Vote on Golden Parachute Compensation (Proposal 2)" beginning on page 96.

Q:

What vote is required to approve the "golden parachute" compensation payable to certain of the Company's named executive officers in connection with the merger?

A:

The affirmative vote of the majority of the shares present in person or represented by proxy and entitled to vote on the proposal is required for approval of the advisory (non-binding) proposal on "golden parachute" compensation.

Q:

What will happen if stockholders do not approve the "golden parachute" compensation at the special meeting?

A:

Approval of the "golden parachute" compensation is not a condition to completion of the merger. The vote with respect to the "golden parachute" compensation is an advisory vote and will not be binding on the Company or Parent. If the merger agreement is adopted by the stockholders and completed, the "golden parachute" compensation may be paid to the Company's named executive officers even if stockholders fail to approve the golden parachute compensation.

Q:

What is a quorum?

A:

A quorum will be present if holders of a majority of the outstanding shares of common stock entitled to vote on a matter at the special meeting are present in person or represented by proxy at the special meeting. If a quorum is not present at the special meeting, the special meeting may be adjourned or

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postponed from time to time until a quorum is obtained. If you submit a proxy, your shares will be counted to determine whether the Company has a quorum even if you abstain or fail to provide voting instructions on any of the proposals listed on the proxy card. If your shares are held in the name of a nominee, and you do not tell the nominee how to vote your shares, these shares will be counted for purposes of determining the presence or absence of a quorum for the transaction of business.

Q:

How many votes do I have?

A:

You have one vote for each share of Interline common stock that you own as of the record date.

Q:

How are votes counted?

A:

Votes will be counted by the inspector of election appointed for the special meeting, who will separately count "FOR" and "AGAINST" votes, abstentions and broker non-votes and separately count votes in respect of each proposal. A "broker non-vote" occurs when a nominee holding shares for a beneficial owner does not receive instructions from the beneficial owner with respect to the merger proposal, or the proposal for "golden parachute" compensation, or the adjournment proposal, counted separately.

Because Delaware law requires the affirmative vote of holders of a majority of the outstanding shares of Interline common stock to approve the adoption of the merger agreement, the failure to vote, broker non-votes and abstentions will have the same effect as voting "AGAINST" the merger proposal.

Because the advisory vote to approve the "golden parachute" compensation and approval of the adjournment proposal require the affirmative vote of the majority of the shares present in person or represented by proxy and entitled to vote thereon and thereat, abstentions will have the same effect as a vote "AGAINST" the "golden parachute" compensation and adjournment proposal, and broker non-votes will have no effect on the outcome of the "golden parachute" compensation and adjournment proposal. See "Adjournment of the Special Meeting (Proposal 3)," beginning on page 98.

Q:

How do I vote my Interline common stock?

A:

Before you vote, you should read this Proxy Statement carefully and in its entirety, including the appendices, and carefully consider how the merger affects you. Then, mail your completed, dated and signed proxy card in the enclosed return envelope or submit your proxy by Internet, by telephone or by mail as soon as possible so that your shares can be voted at the special meeting. For more information on how to vote your shares, see "The Special Meeting—Record Date; Stockholders Entitled to Vote; Quorum; Voting Information" beginning on page 23.

Q:

What happens if I do not vote?

A:

The vote to adopt the merger agreement is based on the total number of shares of Interline common stock outstanding on the record date, and not just the shares that are voted. If you do not vote, it will have the same effect as a vote "AGAINST" the merger proposal. If the merger is completed, whether or not you vote for the merger proposal, you will be paid the merger consideration for your shares of Interline common stock upon completion of the merger, unless you properly exercise your appraisal rights. See "The Special Meeting" and "The Merger (Proposal 1)—Appraisal Rights" beginning on pages 22 and 58, respectively, and Appendix B to this Proxy Statement.

The vote to approve the "golden parachute" compensation is advisory only and will not be binding on the Company or Parent and is not a condition to completion of the merger. If the merger agreement is adopted by the stockholders and completed, the "golden parachute" compensation may be paid to the

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Company's named executive officers even if stockholders fail to approve the golden parachute compensation.

Q:

If the merger is completed, how will I receive cash for my shares?

A:

If the merger agreement is adopted and the merger is consummated, and if you are the record holder of your shares of Interline common stock immediately prior to the effective time of the merger (i.e., you have a stock certificate), you will be sent a letter of transmittal to complete and return to a paying agent to be designated by Parent, referred to herein as the "paying agent." In order to receive the $25.50 per share in cash, without interest and less any applicable withholding taxes, you must send the paying agent, according to the instructions provided, your validly completed letter of transmittal together with your Interline stock certificates and other required documents as instructed in the separate mailing. Once you have properly submitted a completed letter of transmittal, you will receive cash for your shares. If your shares of Interline common stock are held in "street name" by your broker, bank or other nominee, you will receive instructions after the effective time of the merger from your broker, bank or other nominee as to how to effect the surrender of your "street name" shares and receive cash for those shares.

Q:

What happens to my stock options awards if the merger is completed?

A:

Immediately prior to the effective time of the merger, unless otherwise agreed upon in writing between Parent and any such holder, each stock option issued under the Company's equity compensation plans, whether or not then exercisable or vested, will be cancelled and converted into the right to receive an amount in cash equal to, without interest and less applicable withholding taxes, the product of (i) the excess of $25.50 (the per share merger consideration) over the per share exercise price of the applicable stock option and (ii) the aggregate number of shares of common stock that may be acquired upon exercise of such stock option immediately prior to the effective time of the merger.

Q.

What happens to my restricted share unit awards if the merger is completed?

A.

Immediately prior to the effective time of the merger, unless otherwise agreed upon in writing between Parent and any such holder, each restricted share unit granted under the Company's equity compensation plans, will be vested (to the extent not already vested) in accordance with its terms. Further, in connection with the action approving the merger and the merger agreement, the Company's Board of Directors authorized the accelerated vesting of the performance conditions applicable to restricted share units outstanding immediately prior to the consummation of the merger. Under the merger agreement, the Company must accelerate all performance conditions with respect to restricted share units at an amount equal to the maximum of such award. Accordingly, unless otherwise agreed upon between Parent and any such holder, all restricted share units with performance vesting conditions will be deemed satisfied and will vest at the maximum amount of such award as of immediately prior to the consummation of the merger.

Q.

What happens if the merger is not completed?

A.

If the merger agreement is not adopted by the stockholders of the Company or if the merger is not completed for any other reason, the stockholders of the Company will not receive any payment for their shares of Interline common stock in connection with the merger. Instead, Interline will remain an independent public company, Interline common stock will continue to be listed and traded on the New York Stock Exchange and registered under the Exchange Act and the Company will continue to file periodic reports with the SEC with respect to Interline common stock. Under specified circumstances, the Company may be required to pay to Parent, or may be entitled to receive from Parent, a fee with respect to the termination of the merger agreement, as described under "The Merger Agreement—Effect of Termination; Fees and Expenses" beginning on page 92.

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Q:

When should I send in my stock certificates?

A:

You should send your stock certificates together with the letter of transmittal after the merger is consummated and not now. You will receive the letter of transmittal following the consummation of the merger.

Q:

I do not know where my stock certificate is—how will I get my cash?

A:

The materials you are sent after the completion of the merger will include the procedures that you must follow if you cannot locate your stock certificate. This will include an affidavit that you will need to sign attesting to the loss of your stock certificate. The Company may also require that you provide a customary indemnity agreement to the Company in order to cover any potential loss.

Q:

What happens if I sell my shares of Interline common stock before the special meeting?

A:

The record date for stockholders entitled to vote at the special meeting is earlier than the consummation of the merger. If you transfer your shares of Interline common stock after the record date but before the special meeting you will, unless special arrangements are made, retain your right to vote at the special meeting, but will transfer the right to receive the merger consideration to the person to whom you transfer your shares.

Q:

If my shares are held in "street name" by my broker, bank or other nominee, will my broker, bank or other nominee vote my shares for me?

A:

Your broker will not vote your shares on your behalf unless you provide instructions to your broker on how to vote. You should follow the directions provided by your broker regarding how to instruct it to vote your shares. Without those instructions, your shares will not be voted, which will have the same effect as voting "AGAINST" the adoption of the merger agreement and the approval of the advisory (non-binding) vote on the "golden parachute" compensation, but will have no effect for purposes of the proposals to adjourn the special meeting, if necessary or appropriate, or to solicit additional proxies. The instructions set forth below apply to stockholders of record (also referred to as "registered holders") only and not those whose shares are held in the name of a nominee.

Q:

Will my shares held in "street name" or another form of record ownership be combined for voting purposes with shares I hold of record?

A:

No. Because any shares you may hold in "street name" will be deemed to be held by a different stockholder than any shares you hold of record, any shares so held will not be combined for voting purposes with shares you hold of record. Similarly, if you own shares in various registered forms, such as jointly with your spouse, as trustee of a trust or as custodian for a minor, you will receive, and will need to sign and return, a separate proxy card for those shares because they are held in a different form of record ownership. Shares held by a corporation or business entity must be voted by an authorized officer of the entity. Shares held in an individual retirement account must be voted under the rules governing the account.

Q:

What does it mean if I receive more than one set of proxy materials?

A:

This means you own shares of Interline common stock that are registered under different names or are in more than one account. For example, you may own some shares directly as a stockholder of record and other shares through a broker or you may own shares through more than one broker. In these situations, you will receive multiple sets of proxy materials. You must vote, sign and return all of the proxy cards or follow the instructions for any alternative voting procedure on each of the proxy cards that you receive in order to vote all of the shares you own. Each proxy card you receive comes

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with its own prepaid return envelope. If you submit your proxy by mail, make sure you return each proxy card in the return envelope that accompanies that proxy card.

Q:

What if I fail to instruct my broker?

A:

Without instructions, your broker will not vote any of your shares held in "street name." Broker non-votes will be counted for purposes of determining the presence or absence of a quorum. Broker non-votes will have exactly the same effect as a vote "AGAINST" the merger proposal and the advisory (non-binding) vote on "golden parachute" compensation, but will have no effect on the vote on the adjournment proposal.

Q:

When do you expect the merger to be completed?

A:

In order to complete the merger, the Company must obtain the stockholder approval described in this Proxy Statement, the marketing period must have ended, and the other closing conditions under the merger agreement must be satisfied or waived. The parties to the merger agreement currently expect to complete the merger in early to mid September 2012, although the Company cannot assure completion by any particular date, if at all. Because the merger is subject to a number of conditions, the exact timing of the merger cannot be determined at this time.

Q:

What are the U.S. federal income tax consequences of the merger?

A:

The merger will be a taxable event for U.S. federal income tax purposes. Each U.S. holder (as defined in this Proxy Statement) will recognize a taxable gain or loss in an amount equal to the difference between the consideration received in the merger (prior to reduction for any applicable withholding taxes) and the U.S. holder's adjusted tax basis in the shares of Interline common stock surrendered. See "The Merger (Proposal 1)—Material U.S. Federal Income Tax Consequences" beginning on page 62 for a discussion of the material U.S. federal income tax consequences of the merger to certain U.S. holders and certain non-U.S. holders. The tax consequences of the merger will depend on the facts of your own situation. You should consult your tax advisor for a full understanding of the tax consequences of the merger.

Q:

What happens if I do not return a proxy card by mail, vote via the Internet or telephone or attend the special meeting and vote in person?

A:

Your failure to return your proxy card by mail, vote via the Internet or telephone or attend the special meeting and vote in person, will have the same effect as a vote "AGAINST" adoption of the merger agreement.

Q:

May I vote in person?

A:

Yes. You may attend the special meeting and vote your shares in person whether or not you sign and return your proxy card. If your shares are held of record by a broker, bank or other nominee and you wish to vote at the special meeting, you must obtain a proxy from such record holder.

Q:

May I change my vote after I have mailed my signed proxy card?

A:

Yes. You may revoke and change your vote at any time before your proxy card is voted at the special meeting. You can do this in one of three ways:

•

First, you can send a written notice to the Company's corporate secretary stating that you would like to revoke your proxy;

•

Second, you can complete and submit a new proxy by Internet, by telephone or by mail; or

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•

Third, you can attend the meeting and vote in person. Your attendance alone will not revoke your proxy.


If you have instructed a broker, bank or other nominee to vote your shares, you must follow directions received from your broker, bank or other nominee to change those instructions.

Q:

What rights do I have to seek a valuation of my shares?

A:

Under Delaware law, stockholders who do not vote in favor of the merger may exercise appraisal rights, but only if they do not vote in favor of the merger proposal and they otherwise comply with the procedures of Section 262 of the DGCL, which is the appraisal statute applicable to Delaware corporations. See "Appraisal Rights" beginning on page 58. A copy of Section 262 of the DGCL is included as Appendix B to this Proxy Statement.

Q:

What do I need to do now?

A:

You should carefully read this Proxy Statement, including the appendices in their entirety, and consider how the merger would affect you. Please complete, sign, date and mail your proxy card in the enclosed postage prepaid envelope as soon as possible so that your shares may be represented at the special meeting.

Q:

Who can help answer my questions?

A:

If you have questions about the merger agreement or the merger, including the procedures for voting your shares, you should contact Michael Agliata via telephone at (904) 421-1471 or via email at Michael.Agliata@interlinebrands.com. You may also call the Company's proxy solicitor Georgeson Inc., toll-free at 1-888-206-5896.

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INTRODUCTION

        This Proxy Statement and the accompanying form of proxy are being furnished to the Company's stockholders in connection with the solicitation of proxies by the Company's Board of Directors for use at the special meeting to be held on August 29, 2012, at 10:00 a.m. local time at the offices of the Company, located at 701 San Marco Boulevard, Jacksonville, Florida 32207.

        The Company is asking its stockholders to (i) vote on the adoption of the merger agreement, dated as of May 29, 2012, by and among the Company, Parent and Merger Sub and (ii) cast an advisory (non-binding) vote to approve "golden parachute" compensation payable under existing agreements to certain of the Company's named executive officers in connection with the merger.

        If the merger is completed, the Company will continue as the surviving corporation and immediately following the merger, become a wholly owned subsidiary of Parent, and each share of Interline common stock owned by the Company's stockholders immediately prior to the effective time of the merger, other than as provided below, will be converted into the right to receive $25.50 per share in cash, without interest and less any applicable withholding taxes. The following shares of Interline common stock will not be converted into the right to receive the per share merger consideration in connection with the merger: (a) shares of common stock owned by the Company, (b) shares of common stock owned by Parent or Merger Sub, including shares contributed to Parent by the P2 Fund and certain members of Company management or (c) shares of common stock whose holders have not voted in favor of adopting the merger agreement and have demanded and perfected their appraisal rights under Section 262 of the DGCL.

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THE COMPANIES

Interline Brands, Inc.

        Interline Brands, Inc. is a leading national distributor and direct marketer of broad-line maintenance, repair and operations ("MRO") products. The Company stocks approximately 100,000 MRO products in the following categories: janitorial and sanitation ("JanSan"); plumbing; hardware, tools and fixtures; heating, ventilation and air conditioning ("HVAC"); electrical and lighting; appliances and parts; security and safety; and other miscellaneous products. The Company's products are primarily used for the repair, maintenance, remodeling, refurbishment and construction of residential properties and non-industrial facilities.

        Interline's highly diverse customer base includes facilities maintenance customers, which consist of multi-family housing facilities, educational institutions, lodging and health care facilities, government properties and building service contractors; professional contractors who are primarily involved in the repair, remodeling and construction of residential and non-industrial facilities; and specialty distributors, including plumbing and hardware retailers. Interline's customers range in size from individual contractors and independent hardware stores to apartment management companies and national purchasing groups.

        Interline markets and sells its products primarily through fourteen distinct and targeted brands, each of which is recognized in the markets they serve for providing quality products at competitive prices with reliable same-day or next-day delivery. The Wilmar®, AmSan®, CleanSource®, Sexauer®, NCP®, Maintenance USA® and Trayco® brands generally serve Interline's facilities maintenance customers; the Barnett®, Copperfield®, U.S. Lock® and SunStar® brands generally serve Interline's professional contractor customers; and the Hardware Express®, LeranSM and AF Lighting® brands generally serve the Company's specialty distributors customers. Interline's multi-brand operating model, which it believes is unique in the industry, allows Interline to use a single platform to deliver tailored products and services to meet the individual needs of each respective customer group served. Interline reaches its markets using a variety of sales channels, including a sales force of approximately 700 field sales representatives, approximately 360 inside sales and customer service representatives, a direct marketing program consisting of catalogs and promotional flyers, brand-specific websites and a national accounts sales program.

        Interline delivers its products through a network of 55 primary distribution centers and 25 free-standing professional contractor showrooms located throughout the U.S., Canada and Puerto Rico, 52 vendor-managed inventory locations at large customer locations and a dedicated fleet of trucks and third-party carriers. Interline's broad distribution network enables it to provide reliable, next-day delivery service to approximately 98% of the U.S. population and same-day delivery service to most major metropolitan markets in the U.S.

        Please see the Company's Annual Report on Form 10-K for a more complete description of Interline and its business.

Interline Brands, Inc.
701 San Marco Boulevard
Jacksonville, Florida 32207
Telephone: (904) 421-1400

Isabelle Holding Company Inc.

        Parent is a Delaware corporation (which corporation may be converted to a Delaware limited liability company prior to the consummation of the merger) and affiliate of GS Capital Partners VI L.P. and interests of which will be owned, at the closing of the transactions contemplated by the merger agreement, by one or more investment funds managed by P2 Capital Partners, LLC and certain members of Company management, that was formed solely for the purpose of effecting the merger. At the effective time of the merger, Parent will be the direct parent of the surviving company resulting from the merger of Merger Sub

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into the Company. Parent has not conducted any activities other than those incidental to its formation and the transactions contemplated by the merger agreement.

Isabelle Holding Company Inc.
c/o GS Capital Partners VI Fund, L.P.
200 West Street
New York, NY 10282-2198
Attention: Bradley Gross
Fax: 212-357-5505

GS Capital Partners

        Since 1986, the Goldman Sachs Merchant Banking Division and its predecessor business areas have raised 16 private equity and principal debt investment funds aggregating over $82 billion of capital (including leverage). A global leader in private corporate equity investing, the GS Capital Partners family of funds focuses on large, high quality companies with strong management and funding acquisition or expansion across a range of industries and geographies. Founded in 1869, Goldman Sachs is a leading global investment banking, securities and investment management firm that provides a wide range of financial services to a substantial and diversified client base that includes corporations, financial institutions, governments and high-net-worth individuals. For more information, please visit www.gs.com/pia.

P2 Capital Partners, LLC

        P2 Capital Partners, LLC is a New York-based investment firm that applies a private equity approach to investing in the public market. P2 Capital Partners, LLC manages a concentrated portfolio of significant ownership stakes in high quality public companies in which it is an active shareholder focused on creating long-term value in partnership with management. Limited partners of funds managed by P2 Capital Partners, LLC include leading public pension funds, corporate pension funds, endowments, foundations, insurance companies, and high net worth investors.

Isabelle Acquisition Sub Inc.

        Merger Sub, a wholly owned subsidiary of Parent, is a Delaware corporation that was formed solely for the purpose of effecting the merger. At the effective time of the merger, Merger Sub will be merged with and into the Company and the name of the surviving company will be Interline Brands, Inc. Merger Sub has not conducted any activities other than those incidental to its formation and the transactions contemplated by the merger agreement. Upon the completion of the merger, Merger Sub will cease to exist.

Isabelle Acquisition Sub Inc.
c/o GS Capital Partners VI Fund, L.P.
200 West Street
New York, NY 10282-2198
Attention: Bradley Gross
Fax: 212-357-5505

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CAUTIONARY STATEMENTS CONCERNING FORWARD-LOOKING INFORMATION

        This Proxy Statement, the documents incorporated by reference, as well as oral statements made or to be made includes and incorporates by reference statements that are not historical facts. These forward-looking statements are based on the Company's current estimates and assumptions and, as such, involve uncertainty and risk. Forward-looking statements include the information concerning the Company's possible or assumed future results of operations and the Company's plans, intentions and expectations to complete the merger and also include those preceded or followed by the words "anticipates," "believes," "could," "estimates," "expects," "intends," "may," "should," "plans," "targets" and/or similar expressions. They include statements relating to future revenue and expenses, the expected growth of the Company's business and trends and opportunities in the Company's markets.

        These forward-looking statements include, among other things, whether and when the proposed merger will close and whether conditions to the proposed merger will be satisfied. These forward-looking statements also involve known and unknown risks, uncertainties and other factors that include, among others, the failure of the merger to be completed, the time at which the merger is completed, adoption of the merger agreement by the Company's stockholders, and failure by the Company or by Parent or Merger Sub to satisfy conditions to the merger.

        The forward-looking statements are not guarantees of future performance or that the merger will be completed as planned, and actual results may differ materially from those contemplated by these forward-looking statements. In addition to the factors discussed elsewhere in this Proxy Statement, other factors that could cause actual results to differ materially include industry performance, general business, economic, regulatory and market and financial conditions, all of which are difficult to predict. The risk factors discussed herein are also discussed in the documents that are incorporated by reference into this Proxy Statement. These factors may cause the Company's actual results, performance and achievements, or industry results, to be materially different from any future results, performance or achievements expressed or implied by such forward-looking statements.

        Additionally, important factors could cause the Company's actual results to differ materially from such forward-looking statements. Such risk, uncertainties and other important factors include, among others:

•

the satisfaction of the conditions to complete the merger, including the failure of the Company's stockholders to approve the merger;



•

the amount of the costs, fees, expenses and charges related to the merger;



•

the potential adverse effect on the Company's business and operations due to the Company's compliance with certain of the Company's covenants in the merger agreement;



•

the effect of the announcement of the merger on the Company's customer and supplier relationships, operating results and business generally;



•

the Company's inability to retain and, if necessary, attract key employees, particularly while the proposed merger is pending;



•

risks related to diverting management's attention from ongoing business operations;



•

general economic and market conditions;



•

the risk of unforeseen material adverse changes to the Company's business and operations;



•

the risk that required consents to the merger will not be obtained;



•

the risk that the merger may not be completed on the expected timetable, or at all, which may adversely affect the Company's business and the share price of the Interline's common stock;

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•

litigation in respect of the merger;



•

risks relating to recent or future ratings agency actions or downgrades as a result of the announcement of the merger;



•

reduced access to capital markets as the result of the delisting of Interline common stock on the New York Stock Exchange following consummation of the merger;



•

the impact of the Company's substantial leverage on the Company's ability to raise additional capital to fund its operations, on its ability to react to changes in the economy or the Company's industry and on its ability to meet its obligations under its indebtedness;



•

the execution of the merger agreement may impact the ability of the Company to consummate certain transactions in the Company's mergers and acquisitions pipeline as such transactions will require the consent of Parent; and



•

other risks and uncertainties in the Company's filings with the SEC, including the risks set forth in "Item 1A. Risk Factors" in the Company's Annual Report on Form 10-K for the year ended December 30, 2011 (filed with the SEC on February 28, 2012), referred to as the "Form 10-K." See "Where You Can Find More Information".

        These factors may cause the Company's actual results, performance and achievements, or industry results, to be materially different from any future results, performance or achievements expressed or implied by such forward-looking statements.

        Except to the extent required by law, the Company undertakes no obligation to publicly update or revise any forward-looking statement, whether as a result of new information, future events or otherwise. All subsequent written and oral forward-looking statements attributable to the Company or persons acting on the Company's behalf are expressly qualified in their entirety by the cautionary statements contained throughout this Proxy Statement.

        All information contained in this Proxy Statement concerning Parent, Merger Sub, GS Capital Partners and P2 Capital Partners, LLC has been supplied by Parent, Merger Sub, GS Capital Partners and P2 Capital Partners, LLC, as applicable, and has not been independently verified by the Company.

THE SPECIAL MEETING

Time, Place and Purpose of the Special Meeting

        The enclosed proxy is solicited on behalf of the Company's Board of Directors for use at a special meeting of the Company's stockholders to be held on August 29, 2012, at 10:00 a.m., local time, or at any adjournments or postponements thereof, for the purposes set forth in this Proxy Statement and in the accompanying notice of special meeting. The special meeting will be held at the offices of the Company, located at 701 San Marco Boulevard, Jacksonville, Florida 32207.

        At the special meeting, the Company's stockholders are being asked to consider and vote upon a proposal to adopt the merger agreement. The Company's stockholders are also being asked to approve the adjournment of the special meeting, if necessary or appropriate, to solicit additional proxies if there are insufficient votes at the time of the special meeting to adopt the merger agreement. Further, the Company's stockholders are being asked to cast an advisory (non-binding) vote to approve "golden parachute" compensation payable under existing agreements to of the Company's named executive officers in connection with the merger.

        The Company does not expect a vote to be taken on any other matters at the special meeting or any adjournment or postponement thereof. If any other matters are properly presented at the special meeting or any adjournment or postponement thereof for consideration, however, the holders of the proxies will have discretion to vote on these matters in accordance with their best judgment.

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Board Recommendation

        The Company's Board of Directors unanimously (a) approved and declared advisable the merger agreement and the transactions contemplated by the merger agreement, including the merger, (b) determined that the merger agreement and the transactions contemplated by the merger agreement, including the merger, are in the best interests of the Company and the stockholders of the Company and (c) resolved to recommend that the stockholders of the Company adopt the merger agreement. For a discussion of the material factors considered by the Company's Board of Directors in reaching its conclusions, see "The Merger (Proposal 1)—Recommendation of the Company's Board of Directors" beginning on page 34.

        The Company's Board of Directors recommends that you vote "FOR" the proposal to adopt the merger agreement, "FOR" the proposal to approve the "golden parachute" compensation and "FOR" the adjournment of the special meeting, if necessary or appropriate, to solicit additional proxies.

Record Date; Stockholders Entitled to Vote; Quorum; Voting Information

        Only holders of record of Interline common stock at the close of business on July 26, 2012 are entitled to notice of and to vote at the special meeting. At the close of business on July 26, 2012, 31,930,798 shares of Interline common stock were outstanding and entitled to vote. A list of the Company's stockholders will be available for review at the Company's executive offices during regular business hours after the date of this Proxy Statement and through the date of the special meeting. Each holder of record of Interline common stock on the record date will be entitled to one vote for each share held by such holder. The presence, in person or by proxy, of the holders of a majority of the outstanding shares of Interline common stock entitled to vote at the special meeting is necessary to constitute a quorum for the transaction of business at the special meeting.

        All votes will be tabulated by the inspector of election appointed for the special meeting, who will separately tabulate affirmative and negative votes, abstentions and broker non-votes, if any.

        If a stockholder's shares are held of record by a broker, bank or other nominee and the stockholder wishes to vote at the special meeting, the stockholder must obtain from the record holder a proxy issued in the stockholder's name. Brokers who hold shares in "street name" for clients typically have the authority to vote on "routine" proposals when they have not received instructions from beneficial owners. Absent specific instructions from the beneficial owner of the shares, however, brokers are not allowed to exercise their voting discretion with respect to the approval of non-routine matters, such as the merger agreement. Proxies submitted without a vote by brokers on these matters are referred to as "broker non-votes." Abstentions and broker non-votes are counted for purposes of determining whether a quorum exists at the special meeting.

        Proxies received at any time before the special meeting and not revoked or superseded before being voted will be voted at the special meeting. If the proxy indicates a specification, it will be voted in accordance with the specification. If no specification is indicated, the proxy will be voted "FOR" adoption of the merger agreement, "FOR" the approval of the "golden parachute" compensation, "FOR" the approval of the proposal to adjourn the special meeting if there are not sufficient votes to adopt the merger agreement, and in the discretion of the persons named in the proxy with respect to any other business that may properly come before the special meeting or any adjournment or postponement of the special meeting.

        Stockholders may also vote in person by ballot at the special meeting.

        The affirmative vote of holders of a majority of the outstanding shares of Interline common stock is required to adopt the merger agreement. Because adoption of the merger agreement requires the approval of stockholders representing a majority of the outstanding shares of Interline common stock, failure to vote your shares of Interline common stock (including failure to provide voting instructions if you hold

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through a broker, bank or other nominee) will have exactly the same effect as a vote against the merger agreement. However, failure to vote your shares (including failure to provide voting instructions if you hold through a broker, bank or other nominee) will have no effect on the vote to approve the "golden parachute" compensation.

        The vote to approve the "golden parachute" compensation is advisory only and will not be binding on the Company or Parent and is not a condition to consummation of the merger. If the merger agreement is adopted by the stockholders and completed, the "golden parachute" compensation may be paid to the Company's named executive officers even if stockholders fail to approve the golden parachute compensation.

        The approval of the proposal to adjourn the special meeting if there are not sufficient votes to adopt the merger agreement requires the affirmative vote of stockholders holding a majority of the shares present in person or by proxy at the special meeting and entitled to vote thereon. The persons named as proxies may propose and vote for one or more adjournments of the special meeting, including adjournments to permit further solicitations of proxies.

        The P2 Fund, which, together with P2 Capital Master Fund VI, L.P., collectively owns as of May 25, 2012, 7.9% of the outstanding shares of the Company, has entered into an investor support agreement with Parent, dated as of May 29, 2012, pursuant to which the P2 Fund has agreed to vote, and to use best efforts to cause P2 Capital Master Fund VI, L.P. to vote, its shares of Interline common stock "FOR" the adoption of the merger agreement and the approval of the merger and any related proposal in furtherance of the transactions contemplated by the merger agreement.

        Please do not send in stock certificates at this time. If the merger is completed, you will be sent a letter of transmittal regarding the procedures for exchanging the existing Company's stock certificates for the payment of $25.50 per share in cash, without interest and less any applicable withholding taxes.

How You Can Vote

        Each share of Interline common stock outstanding on July 26, 2012, the record date for stockholders entitled to vote at the special meeting, is entitled to one vote at the special meeting. The affirmative vote of holders of a majority of the outstanding shares of Interline common stock is required to adopt the merger agreement. Because adoption of the merger agreement requires the approval of stockholders representing a majority of the outstanding shares of Interline common stock, failure to vote your shares of Interline common stock (including failure to provide voting instruction if you hold through a broker, bank or other nominee) will have exactly the same effect as a vote against the merger agreement.

        You may vote your shares in any of the following ways:

•

Submitting a Proxy by Mail.  If you choose to have your shares voted at the special meeting by submitting a proxy by mail, simply mark your proxy, date and sign it, and return it in the postage-paid envelope provided.



•

Submitting a Proxy by Telephone.  You can have your shares voted at the special meeting by submitting a proxy by telephone by calling the toll-free number on the proxy card until 11:59 p.m. Eastern Time on August 28, 2012. You will then be prompted to enter the control number printed on your proxy card and to follow the subsequent instructions. Submitting a proxy by telephone is available 24 hours a day. If you submit a proxy by telephone with respect to a proxy card, do not return that proxy card.



•

Submitting a Proxy by Internet.  You can also have your shares voted at the special meeting by submitting a proxy via the Internet until 11:59 p.m. Eastern Time on August 28, 2012. The website for submitting a proxy via the Internet is www.proxyvote.com, and is available 24 hours per day. Instructions on how to submit a proxy via the Internet are located on the proxy card enclosed with

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this Proxy Statement. Have your proxy card in hand when you access the web site and follow the instructions to obtain your records and create an electronic voting form. If you submit a proxy via the Internet with respect to a proxy card, you should not return that proxy card.

•

Voting in Person.  You can also vote by appearing and voting in person at the special meeting.

        If you choose to have your shares of Interline common stock voted at the special meeting by submitting a proxy, your shares will be voted at the special meeting as you indicate on your proxy card. If no instructions are indicated on your signed proxy card, all of your shares of Interline common stock will be voted "FOR" the adoption of the merger agreement, "FOR" the approval of the "golden parachute" compensation and "FOR" the approval of the proposal to adjourn the special meeting, if necessary, to solicit additional proxies in the event that there are not sufficient votes at the time of the special meeting to approve the proposal to adopt the merger agreement. You should return a proxy even if you plan to attend the special meeting in person.

Proxies; Revocation

        Any person giving a proxy pursuant to this solicitation has the power to revoke and change it any time before it is voted. It may be revoked and/or changed at any time before it is voted at the special meeting by:

•

giving written notice of revocation to the Company's corporate secretary;



•

submitting another proper proxy by Internet, by telephone or by a later-dated written proxy; or



•

attending the special meeting and voting by paper ballot in person. Your attendance at the special meeting alone will not revoke your proxy.

        If your Interline shares are held in the name of a bank, broker, trustee or other holder of record, including the trustee or other fiduciary of an employee benefit plan, you must obtain a proxy, executed in your favor from the holder of record, to be able to vote at the special meeting.

Expenses of Proxy Solicitation

        The Company will pay the costs of soliciting proxies for the special meeting. Officers, directors and employees of the Company may solicit proxies; however, they will not be paid additional or special compensation for soliciting proxies. The Company will also request that individuals and entities holding shares in their names, or in the names of their nominees, that are beneficially owned by others, send proxy materials to and obtain proxies from, those beneficial owners, and will reimburse those holders for their reasonable expenses in performing those services. Georgeson Inc. has been retained by the Company to assist it in the solicitation of proxies, using the means referred to above, and will receive a fee of approximately $10,500. The Company will reimburse Georgeson Inc. for reasonable expenses and costs incurred by Georgeson Inc. in connection with its services and will indemnify Georgeson Inc. for certain losses.

Adjournments and Postponements

        Although the Company does not expect to do so, if the Company has not received sufficient proxies to constitute a quorum or sufficient votes for adoption of the merger agreement, the special meeting may be adjourned or postponed for the purpose of soliciting additional proxies. The proposal to approve the adjournment or postponement of the special meeting, if necessary or appropriate, to solicit additional proxies requires the affirmative vote of a majority of the shares of Interline common stock present or represented by proxy at the special meeting and entitled to vote on the matter. Any signed proxies received by the Company that approve the proposal to adjourn or postpone the special meeting will be voted in favor of an adjournment or postponement in these circumstances. Any adjournment or postponement of

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the special meeting for the purpose of soliciting additional proxies will allow stockholders who have already sent in their proxies to revoke them at any time prior to their use.

Rights of Stockholders Who Object to the Merger

        Stockholders are entitled to statutory appraisal rights under the DGCL in connection with the merger. This means that holders of Interline common stock who do not vote in favor of the adoption of the merger agreement may be entitled to have the value of their shares determined by the Court of Chancery of the State of Delaware, and to receive payment based on that valuation instead of receiving the $25.50 per share merger consideration. The ultimate amount received in an appraisal proceeding may be more than, the same as or less than the amount that would have been received under the merger agreement.

        To exercise appraisal rights, a dissenting holder of Interline common stock must submit a written demand for appraisal to the Company before the vote is taken on the merger agreement and must NOT vote in favor of the adoption of the merger agreement. Failure to follow exactly the procedures specified under the DGCL will result in the loss of appraisal rights. See "The Merger (Proposal 1)—Appraisal Rights" beginning on page 58 and Appendix B to this Proxy Statement.

Other Matters

        The Company's Board of Directors is not aware of any business to be brought before the special meeting other than that described in this Proxy Statement. If, however, other matters are properly presented at the special meeting, the persons named as proxies will vote in accordance with their best judgment with respect to those matters.

Questions and Additional Information

        If you have questions about the special meeting or the merger after reading this proxy, or if you would like additional copies of this Proxy Statement or the proxy card, you should contact the Company's proxy solicitor, Georgeson Inc., toll-free at 1-888-206-5896.

THE MERGER (PROPOSAL 1)

Background of the Merger

        From time to time, the Company's Board of Directors and the Company's management have evaluated strategic alternatives relating to the Company's business, including prospects for acquisitions, the sale of individual business segments, stock repurchases, debt refinancing and other potential strategic transactions, each with a view towards maximizing stockholder value.

        In connection with its ongoing evaluation of strategic alternatives relating to the Company, at regularly scheduled meetings, the Company's Board of Directors has received financial updates from the Company's management. During such meetings, the Company's Board of Directors has discussed significant items that impacted the Company's results of operations, including in particular, results of operations of the Company's business, industry and general economic conditions and management's outlook for the Company's business and the industry.

        In mid-September, the Company, through Barclays, which had a long-standing investment banking relationship with the Company, received an unsolicited inquiry from a representative of Party A, a well-known private equity firm, regarding a potential acquisition of the Company. During that initial contact, Party A expressed a desire to meet with the Company to discuss such a potential transaction.

        Also, in October 2011, a director of the Company received an initial inquiry from a representative of Party B, another well-known private equity firm, indicating that it was interested in a potential acquisition of the Company.

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        At a special telephonic meeting of the Company's Board of Directors on October 14, 2011, at which representatives from Paul, Weiss, Rifkind, Wharton & Garrison LLP ("Paul, Weiss") participated, the Company's Board of Directors discussed the recent indications of interest from Party A and Party B and discussed a process for exploring potential strategic interest in the Company. The Company's Board of Directors determined that Michael J. Grebe, the Company's Chief Executive Officer (the "Chief Executive Officer"), and John J. Gavin, an independent director serving on the Company's Board of Directors (the "Lead Independent Director"), should engage in preliminary discussions with Party A to discuss its potential interest in the Company. Also at this meeting, Paul, Weiss made a presentation to the Company's Board of Directors regarding their fiduciary and other duties in connection with a possible sale transaction involving the Company, including with respect to the process of evaluating expressions of interest by third parties to potentially acquire the Company as well as the evaluation of potential strategic alternatives.

        On October 18, 2011, the Chief Executive Officer and Lead Independent Director of the Company held preliminary discussions with a representative of Party A regarding a potential acquisition of the Company. During such discussions, no indication of value or consideration was given by or discussed with Party A and Party A did not initiate substantive discussions with the Company again until early in 2012.

        On November 16, 2011, the Company, through its Chief Executive Officer and Lead Independent Director, received a further verbal expression of interest from a representative of Party B regarding a potential acquisition of the Company. At such time, Party B expressed its interest in acquiring the Company at a value of $19 to $20 per share. The closing price of the Company's common stock on November 16, 2011 was $14.66 per share.

        At an in-person meeting of the Company's Board of Directors on November 17, 2011, the Company's Board of Directors further discussed the recent unsolicited expressions of interest from Party A and Party B. Following such discussion, the Company's Board of Directors agreed that it should engage an investment bank to assist the Company's Board of Directors in evaluating the recent indications of interest from Party A and Party B and potential strategic alternatives. Due to its familiarity with the Company and long-standing investment banking relationship and its familiarity with the industry in which the Company operates, the Company's Board of Directors agreed to engage Barclays to act as the Company's financial advisor in connection with its review of strategic alternatives. In addition, the Company agreed to engage Paul, Weiss as the Company's outside legal counsel in any such potential sale process.

        At a special telephonic meeting of the Company's Board of Directors on November 27, 2011, at which representatives from Paul, Weiss participated, the Company's Board of Directors discussed a review of strategic alternatives, including a potential sale process, and also discussed the Company's Board of Directors fiduciary obligations with respect to the receipt, consideration and handling of unsolicited expressions of interest by third parties to potentially acquire the Company. The Company's Board of Directors also discussed potential responses to the recent expressions of interest, and discussions related thereto, with Party A and Party B, including, among other things, the process to be followed by the Company's Board of Directors in evaluating any transaction to sell or merge the Company, the impact of a potential transaction to sell and/or merge the Company would have on the Company, and the potential due diligence process with respect to any potential acquirors.

        On December 7, 2011, the Company entered into an engagement letter with Barclays pursuant to which Barclays agreed to act as the Company's financial advisor.

        On December 12, 2011, a representative of P2 Capital Partners, LLC, the manager of the P2 Fund and P2 Capital Master Fund VI, L.P., such funds holding at that time approximately 7.9% of the outstanding common stock of the Company, expressed to the Chief Executive Officer an interest in discussing a potential acquisition of the Company with the assistance of another financial sponsor (which was not identified at that time); however P2 Capital Partners, LLC did not at this time provide a specific price at which it might be willing to acquire the Company. No specific offer was made at this time.

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        At a special telephonic meeting of the Company's Board of Directors on December 16, 2011, at which representatives from Barclays and Paul, Weiss participated, following a review of the Board of Director's fiduciary and other duties, the Company's management presented the Company's five-year business plan, which was then discussed and adopted by the Company's Board of Directors. Additionally, the Chief Executive Officer informed the Company's Board of Directors of his recent communication with P2 Capital Partners, LLC which had yet to provide a purchase price range or disclose specific funding sources. Given P2 Capital Partners, LLC's lack of specificity with respect to its interest, the Company's Board of Directors agreed not to take any action with respect to P2 Capital Partners, LLC's expression of interest at that time.

        At a special telephonic meeting of the Company's Board of Directors on December 20, 2011, Barclays reviewed the Company's alternatives to assist the Company's Board of Directors in developing responses to recent inbound expressions of interest in light of the Company's five-year business plan and then current market and industry conditions. Additionally, following discussion regarding the indication of interest by Party B in light of the foregoing, the Company's Board of Directors agreed that Party B would have to materially increase its offer price in order for the Company to continue to engage in discussions with Party B regarding a potential transaction, and authorized management to enter into a non-disclosure agreement and share confidential information with Party B in order to determine if Party B would be able to materially increase its offer price.

        At the request of the Company's Board of Directors, following the December 20, 2011 meeting, a representative of Barclays relayed to Party B that the purchase price initially suggested by Party B was not compelling and did not fairly value the Company and that if Party B was willing to consider materially increasing its offer, the Company would be willing to enter into a non-disclosure agreement and share information on a confidential basis. Thereafter, Party B confirmed to Barclays that it could potentially increase its proposed offer price if it was permitted access to certain confidential information regarding the Company.

        On January 4, 2012, at the request of Party A, which had not contacted the Company or Barclays since the October 18, 2011 meeting, the Chief Executive Officer met with a representative of Party A, who informed him that Party A had recently acquired approximately 3% of the Company's outstanding common stock and remained interested in a potential transaction to acquire the Company. However, Party A did not make a specific offer to acquire the Company nor did it propose a price for any such potential transaction at this time.

        On January 6, 2012, following negotiation of its terms, and with the approval of the Lead Independent Director, the Company entered into a non-disclosure agreement with Party B.

        Later on January 6, 2012, at a special telephonic meeting of the Company's Board of Directors, at which representatives from Barclays and Paul, Weiss participated, the Company's Board of Directors agreed that the Company should enter into a non-disclosure agreement and engage in discussions with Party A so long as Party A would first propose a range of purchase price for a potential transaction that would be of sufficient value to allow for discussions to continue in view of Party B's previous proposal. At this time, the Company's Board of Directors and its advisors also discussed recent communications with P2 Capital Partners, LLC and determined that no further discussions were warranted due to the continuing lack of information relating to both potential purchase price and potential financing sources.

        On January 7, 2012, the Chief Executive Officer and a representative of Party A discussed Party A's continued interest in a possible acquisition of the Company. Party A informed the Chief Executive Officer that it was considering a price of $20 per share and that Party A would be willing to consider a higher price after it had an opportunity to speak with the Company's management and conduct due diligence. The closing price of the Company's common stock on January 6, 2012 was $16.02 per share.

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        On January 9, 2012, representatives of the Company met with representatives of Party B to provide a management presentation to Party B.

        At a special telephonic meeting of the Company's Board of Directors on January 17, 2012, at which representatives from Paul, Weiss and Barclays participated, the Company's Board of Directors was provided with updates to recent discussions with Parties A and B and the Company's Board of Directors discussed appropriate next steps in connection therewith. The Company's Board of Directors determined that Party A's offer price warranted further discussions with Party A to see if, following a management presentation, a greater proposed valuation could be obtained from Party A. The Chief Executive Officer informed the Company's Board of Directors that the Company was finalizing a non-disclosure agreement with Party A and that the Company's management would be prepared to meet with Party A in late January or early February 2012.

        At the request of the Company's Board of Directors, Barclays had a follow-up call with a representative of Party B on January 20, 2012, at which time Party B indicated that it would be prepared to increase its price modestly, but would not be able to do so by a material amount, as had been requested by the Company's Board of Directors. As a result, discussions with Party B regarding a potential transaction did not continue.

        On January 25, 2012, the Company entered into a non-disclosure agreement with Party A. On February 3, 2012, representatives of the Company met with representatives of Party A to provide a management presentation to Party A.

        In early February 2012, a representative of P2 Capital Partners, LLC contacted the Chief Executive Officer and expressed continuing interest in exploring the possibility of acquiring the Company. However, P2 Capital Partners, LLC did not provide a specific proposed purchase price for the acquisition of the Company at this time but indicated that it would be at a significant premium to the then current market price of approximately $20.56. The Chief Executive Officer indicated to P2 Capital Partners, LLC that he would relay the indicated interest to the Company's Board of Directors for further consideration.

        At an in-person meeting of the Company's Board of Directors on February 15, 2012, at which representatives from Paul, Weiss and Barclays participated, the Company's Board of Directors was informed that discussions with Party B had ended due to Party B's unwillingness to agree to materially increase its offer price. The Company's Board of Directors was then informed that the Company had entered into a non-disclosure agreement with Party A and was provided with details regarding the recent management presentation given to Party A. The Company's Board of Directors then concluded that in order for the Company to continue discussions with Party A regarding a potential transaction, Party A would have to materially increase its offer price. In addition, the Company's Board of Directors was informed of the further general expression of interest received from P2 Capital Partners, LLC in early February. When informed of P2 Capital Partners, LLC's continued interest, the Company's Board of Directors requested that Barclays seek to obtain further clarity and specificity as to P2 Capital Partners, LLC's proposed valuation of the Company (including clarity as to what it meant by a potential offer at a "significant premium") and the identity of the potential financial sponsor with which P2 Capital Partners, LLC was contemplating making its offer to acquire the Company to determine whether further discussions with P2 Capital Partners, LLC were warranted.

        Shortly after the February 15, 2012 meeting of the Company's Board of Directors, at the direction of the Company's Board of Directors, representatives of Barclays notified a representative of Party A that in order for the Company to continue discussions with Party A regarding a potential transaction, Party A would have to materially increase its offer price. The representative of Party A responded that Party A would wait until after the Company's earnings announcement scheduled for February 24, 2012 before taking any further action regarding its proposed offer price.

        On February 24, 2012, the Company released its financial results for the fourth quarter of fiscal 2011.

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        On February 29, 2012, representatives of P2 Capital Partners, LLC met with the Chief Executive Officer as part of a regularly scheduled investors relations meeting. At that meeting, representatives of P2 Capital Partners, LLC identified GS Capital Partners as the potential financial sponsor with which P2 Capital Partners, LLC was contemplating making its offer to acquire the Company. In addition, P2 Capital Partners, LLC, indicated that it had an interest in acquiring the Company at a premium of 30% relative to the Company's then-current stock price of $20.56.

        On March 6, 2012, at a meeting with representatives of Barclays, representatives of P2 Capital Partners, LLC and GS Capital Partners separately delivered unsolicited indications of interest to acquire the Company at a price per share in the range of $25.50 to $28, subject to completion of their due diligence investigation. The closing price of the Company's common stock on March 6, 2012 was $20.20 per share.

        At a special telephonic meeting of the Company's Board of Directors on March 10, 2012, at which representatives from Paul, Weiss and Barclays participated, Barclays informed the Company's Board of Directors that it had expressed to Party A the need for an increased offer price and, since that communication, had not received any response from Party A. Barclays then informed the Company's Board of Directors of the interest and valuation indicated by each of P2 Capital Partners, LLC and GS Capital Partners. The Company's Board of Directors agreed that the Company should proceed with discussions with each of P2 Capital Partners, LLC and GS Capital Partners and that the Company enter into non-disclosure agreements with each of them.

        On March 19, 2012 and March 22, 2012, the Company entered into separate non-disclosure agreements with each of GS Capital Partners and P2 Capital Partners, LLC, respectively. On March 23, 2012, representatives of the Company provided a management presentation to representatives of GS Capital Partners. Following such presentation, each of P2 Capital Partners, LLC and GS Capital Partners separately reaffirmed to Barclays their respective proposed offers of $25.50 to $28 per share. The closing price of the Company's common stock on March 23, 2012 was $21.80 per share.

        On March 23, 2012, a representative from Party A contacted the Chief Executive Officer to let the Company know that Party A was continuing to monitor the stock price of the Company, but no offer was made by Party A at that time.

        On April 2, 2012, a representative of each of P2 Capital Partners, LLC and GS Capital Partners contacted representatives of Barclays to adjust their respective proposed offer ranges to $26 to $28 per share.

        At a special telephonic meeting of the Company's Board of Directors on April 4, 2012, at which representatives from Paul, Weiss and Barclays participated, Barclays informed the Company's Board of Directors of the continued interest of each of P2 Capital Partners, LLC and GS Capital Partners in a potential acquisition of the Company at a price of $26 to $28 per share and each entity's desire to begin the due diligence process in order to confirm a final offer price. Barclays also informed the Company's Board of Directors that P2 Capital Partners, LLC and GS Capital Partners had each engaged separate external advisors to assist them in conducting due diligence. After consultation with Barclays and Paul, Weiss, the Company's Board of Directors unanimously agreed to continue discussions with each of P2 Capital Partners, LLC and GS Capital Partners, including the completion of a due diligence process and the potential negotiation of a merger agreement. The Company's Board of Directors also agreed that certain members of the Company's management, accompanied by representatives of Barclays, were authorized to meet with representatives of P2 Capital Partners, LLC and GS Capital Partners to provide a further management presentation. Additionally, the Company's Board of Directors reaffirmed that the Company's management was not authorized to discuss management compensation or employment arrangements until a final purchase price, if any, had been confirmed by GS Capital Partners and/or P2 Capital Partners, LLC and substantial progress had been made on definitive transaction documentation. Additionally, the Board of Directors discussed a potential process for exploring strategic interest in the Company, including identifying companies operating in the Company's sectors that were most likely to have an interest in

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pursuing a transaction with the Company and the timing of potentially soliciting indications of interest from these parties with regard to a possible transaction with the Company in light of the recent indications of interest from Party A, Party B, P2 Capital Partners, LLC and GS Capital Partners.

        Between April 4, 2012 and May 29, 2012, each of P2 Capital Partners, LLC and GS Capital Partners engaged in an extensive due diligence review of the Company, during which time an electronic dataroom was established and opened to allow each of P2 Capital Partners, LLC and GS Capital Partners, and their respective advisors, to conduct due diligence on the Company.

        On April 12, 2012, representatives of the Company met with representatives of P2 Capital Partners, LLC and GS Capital Partners to provide a management presentation to P2 Capital Partners, LLC and GS Capital Partners and their respective advisors and potential financing sources.

        On April 13, 2012, Debevoise & Plimpton LLP ("Debevoise"), counsel to P2 Capital Partners, LLC, sent to Paul, Weiss a draft merger agreement. Shortly after receipt of the draft merger agreement, on a telephone conference to discuss material issues raised by the draft merger agreement, Paul, Weiss discussed with Debevoise, among other things, the need to include a "go-shop" provision in the merger agreement.

        At a special telephonic meeting of the Company's Board of Directors on April 18, 2012, at which representatives from Paul, Weiss and Barclays participated, the Company's Board of Directors was informed of the current status of the merger agreement being negotiated with P2 Capital Partners, LLC and GS Capital Partners and that GS Capital Partners had requested meetings with certain members of the Company's management and Barclays the following week in New York.

        On April 22, 2012, Debevoise and Fried, Frank, Harris, Shriver & Jacobson LLP ("Fried Frank"), counsel to GS Capital Partners, sent to Paul, Weiss draft equity commitment letters and limited guarantees from the P2 Fund and GS Capital Partners, respectively.

        During April 2012, representatives of Paul, Weiss, Debevoise and Fried Frank, conducted negotiations regarding the terms of the merger agreement and the ancillary documents, including the equity commitment letters and limited guarantees, and exchanged revised drafts of all such documents.

        On April 23, 2012, Messrs. Grebe and Sweder of the Company's management and representatives of Barclays met with senior management of GS Capital Partners and P2 Capital Partners, LLC and on April 24, 2012 those individuals met with the investment committee of GS Capital Partners. Shortly after the meeting concluded on April 24, 2012, GS Capital Partners informed Barclays that GS Capital Partners was going to require additional time to conduct additional due diligence to determine whether it would be able to proceed with a potential transaction with the Company without participation of a partner. Barclays was also informed at this time that P2 Capital Partners, LLC would not be proceeding with a proposed transaction with the Company.

        At a special telephonic meeting of the Company's Board of Directors on April 25, 2012, at which representatives from Paul, Weiss and Barclays participated, the Company's Board of Directors was provided with updates on recent discussions with P2 Capital Partners, LLC and GS Capital Partners, including that P2 Capital Partners, LLC had determined to cease participation in a potential acquisition of the Company and that GS Capital Partners had stated that it needed additional time to determine whether to proceed with the negotiation of a definitive merger agreement relating to the sale of the Company. In light of these developments, the Company's Board of Directors determined that the Company's advisors should suspend work with respect to transaction documents until such time as GS Capital Partners was able to complete its due diligence review of the Company and reaffirm its commitment to consummate the transaction. Additionally, the Company's Board of Directors discussed the timing of potentially soliciting indications of interest from strategic parties with regard to a possible transaction with the Company in light of the recent developments with P2 Capital Partners, LLC and GS Capital Partners, as well as the number of strategic parties to be contacted given that the merger agreement would likely include a "go shop"

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provision, and concluded that a limited number of solicitations of key strategic parties should be commenced after greater certainty regarding GS Capital Partners' commitment to consummate the transaction had been obtained.

        On May 8, 2012, the Company released its financial results for the first quarter of fiscal 2012. On the evening of May 8, 2012, GS Capital Partners contacted Barclays and indicated that it was prepared to proceed with the transaction at a price of $25.50 per share, lower than the range of $26 to $28 that GS Capital Partners had previously indicated to the Company. The closing price of the Company's common stock on May 8, 2012 was $19.72 per share.

        On May 10, 2012, the Company held its 2012 annual meeting of stockholders.

        Also on May 10, 2012, the Company's Board of Directors met and formed a transaction committee comprised of three independent directors to evaluate the transaction proposal from GS Capital Partners and other potential transactions involving the potential acquisition of the Company, which consisted of Gideon Argov, John J. Gavin and Barry J. Goldstein (the "Transaction Committee"). Following deliberations and discussions with the Transaction Committee, the Company's Board of Directors instructed Barclays to request GS Capital Partners to submit its best and final offer price in order for discussions regarding a possible transaction to continue. The Board of Directors also confirmed that Barclays should now solicit indications of interest with regard to a possible acquisition of the Company from three potential strategic acquirers, previously identified by Barclays as companies that were likely to have a potential interest in pursuing a transaction with the Company, to gauge possible market interest in a potential acquisition of the Company. Following such meeting, as instructed by the Company's Board of Directors, Barclays called GS Capital Partners to request its best and final offer.

        On the morning of May 11, 2012, at the direction of the Company's Board of Directors, representatives of Barclays solicited indications of interest with regard to a possible acquisition of the Company from the three potential strategic acquirers. Later that day, after such calls had been made, GS Capital Partners informed Barclays that its offer price was $25.00 per share. GS Capital Partners cited general concerns in the equity and financing markets and noted the Company's declining stock price since March 23, 2012, when GS Capital Partners had indicated its proposed offer in the range of $25.50 to $28 per share. The closing price of the Company's common stock on May 11, 2012 was $18.03 per share.

        The Transaction Committee convened on May 12, 2012 and instructed Barclays to call GS Capital Partners on May 14. 2012 and inform them that the Company would be unwilling to proceed with a transaction at an offer price of less than $25.50 per share, which information Barclays conveyed to GS Capital Partners, on May 14, 2012. Later on May 14, 2012, GS Capital Partners confirmed to Barclays its intention to continue with the transaction at a price of $25.50 per share. The closing price of the Company's common stock on May 14, 2012 was $17.64 per share.

        In addition, on May 14, 2012, the strategic parties contacted by Barclays responded to the requests for indications of interest with respect to a potential transaction with the Company. Strategic Party 1 indicated that it might have an interest but would be unable to move forward to review the opportunity for a period of at least 30 days due to other strategic priorities. Strategic Party 2 informed Barclays that it was not interested in acquiring the entire Company but only potentially acquiring selected assets. Strategic Party 3 informed Barclays that it was not interested in acquiring the Company.

        On May 15, 2012, Messrs. Grebe, Sweder and John Ebner, the Company's Chief Financial Officer, and a representative of Paul, Weiss met with representatives of GS Capital Partners at an in-person meeting to discuss, among other things, GS Capital Partners' proposed timetable for completion of the merger and its proposal for financing the merger. With the prior consent of the Company's Board of Directors given the proposed offer price, GS Capital Partners also discussed its expectations regarding management's equity participation in the merger and the surviving corporation.

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        On May 16, 2012, Fried Frank, counsel to GS Capital Partners, sent to Paul, Weiss a mark-up of the draft merger agreement.

        At a special telephonic meeting of the Company's Board of Directors on May 16, 2012, at which representatives from Paul, Weiss and Barclays participated, the Company's Board of Directors was provided with updates regarding the calls made by Barclays to the three potential strategic acquirers. The Company's Board of Directors also discussed key provisions of the draft merger agreement with Paul, Weiss.

        On May 21, 2012, Party A again contacted the Chief Executive Officer to express an interest in acquiring the Company, and indicated its understanding that a successful offer would need to exceed $23 per share to be acceptable. Given the non-specific nature of this indicative price range, which was in any event below the confirmed offer price of GS Capital Partners, that GS Capital Partners had already substantially completed its due diligence investigation of the Company, while Party A had not yet undertaken significant due diligence efforts and that potential delay and disruption to the process could result from engaging with Party A at this time, the Company's Board of Directors determined not to engage with Party A at this time.

        On May 22, 2012, Paul, Weiss engaged in negotiations with Fried Frank regarding the terms of the merger agreement and the ancillary documents. Following such meeting, between May 22, 2012 and May 29, 2012, representatives of the Company, Paul, Weiss, GS Capital Partners and Fried Frank continued negotiations regarding the terms of the merger agreement and the ancillary documents.

        On May 23, 2012, the Company's Board of Directors held an in-person meeting attended by representatives of Paul, Weiss and Barclays to review the current status of negotiations with GS Capital Partners. The Company's Board of Directors again reviewed with Barclays the indications of interest received from, and communications with, Parties A and B and P2 Capital Partners, LLC and GS Capital Partners and each of the strategic parties from which indications of interest regarding a possible acquisition of the Company had been solicited. Representatives of Paul, Weiss reviewed with the Company's Board of Directors its fiduciary and other duties and legal obligations in the context of the proposed transaction and discussed the terms of the current drafts of the merger agreement and ancillary documents being negotiated with GS Capital Partners. Representatives of Barclays reviewed its financial analyses relating to the proposed purchase price of $25.50 per share. The Company's Board of Directors agreed to meet again on May 28, 2012 to determine whether it should approve a transaction with GS Capital Partners.

        On May 25, 2012, representatives of GS Capital Partners relayed to representatives of the Company that due to changes in the financing markets, in order for GS Capital Partners to proceed with the proposed transaction, it would require either a new closing condition in the merger agreement that as of the closing date the available cash of the Company and its subsidiaries would not be less than $50 million or a purchase price reduction of approximately $0.50 per share.

        Later on May 25, 2012, at a telephonic meeting of the Transaction Committee that was also attended by representatives of Paul, Weiss and Barclays, the Transaction Committee discussed the recent developments with respect to GS Capital Partners and concluded that the Company would not agree to a purchase price reduction but that given the Company's historical, current and projected cash balances, that, subject to the approval of the Company's Board of Directors, the Company could likely agree to the inclusion of the proposed new closing condition.

        On May 27, 2012, P2 Capital Partners, LLC informed Barclays that it expected to participate in the transaction and that it would be making an equity commitment through the P2 Fund on similar terms to GS Capital Partners except that the P2 Fund's commitment would be comprised of shares of common stock of the Company and cash.

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        Between May 27, 2012 and May 29, 2012, representatives of the Company, Paul, Weiss, Fried Frank, Debevoise, P2 Capital Partners, LLC and GS Capital Partners continued negotiations regarding the terms of the merger agreement and ancillary agreements, including the equity and debt commitment letters and the limited guarantees. With the prior consent of the Company's Board of Directors, during this time, representatives of GS Capital Partners also continued negotiations with the Company's chief executive officer regarding the terms of his investment in Parent, the expected investment in Parent by other members of senior management, and the terms of a new equity plan, and awards granted thereunder, to be sponsored by Parent post-closing.

        On May 28, 2012, Debevoise sent to Paul, Weiss a revised draft equity commitment letter and limited guarantee from P2 Capital Partners, LLC.

        On May 28, 2012, the Company's Board of Directors held a telephonic meeting attended by representatives of Paul, Weiss and Barclays to consider entering into the merger agreement with an affiliate of P2 Capital Partners, LLC and GS Capital Partners LP. Representatives of Paul, Weiss reviewed with the Company's Board of Directors the terms of the current drafts of the merger agreement and ancillary documents and the changes made following the resolution of the open issues since the last meeting of the Company's Board of Directors. A representative of Barclays again reviewed its financial analyses relating to the proposed purchase price of $25.50 per share, and Barclays also rendered its oral opinion, which opinion was subsequently confirmed in a written opinion dated May 29, 2012, to the Company's Board of Directors to the effect that, as of that date and based upon and subject to the qualifications, limitations and assumptions stated in its written opinion, the per share merger consideration of $25.50 offered to the Company's stockholders in the merger was fair, from a financial point of view, to such stockholders (other than P2 Capital Partners, LLC and its affiliated funds). See "The Merger (Proposal 1)—Opinion of the Company's Financial Advisor" in this proxy statement for more information about the Barclays opinion. After further discussion of the terms of the draft merger agreement and ancillary documents, consideration of other relevant issues, and a variety of business, financial and market factors, including those set forth below under "The Merger (Proposal 1)—Reasons for the Merger" and the delivery of the oral fairness opinion, the Company's Board of Directors unanimously determined that it was advisable and in the best interests of the Company and its stockholders to adopt and approve the merger agreement and resolved that it recommend to the Company's stockholders that they vote in favor of the approval of the merger agreement.

        Following this meeting, on May 29, 2012, the parties entered into the merger agreement and other transaction documents, and the transaction was publicly announced on May 29, 2012.

        The merger agreement provides that, until 11:59 p.m. (New York City time) on June 28, 2012, the Company was permitted to solicit, initiate, facilitate and encourage any inquiries regarding any proposal or offer that constituted an acquisition proposal, including by way of providing non-public information, and enter into and maintain discussions or negotiations with respect to acquisition proposals or other proposals that could lead to acquisition proposals, or otherwise cooperate, assist, participate in or facilitate any such discussions or negotiations (subject to compliance with the terms of the merger agreement). Barclays, on behalf of the Company, contacted 54 potential bidders during the go-shop period. However, the Company did not receive any alternative acquisition proposals during such period.

Recommendation of the Company's Board of Directors

        After careful consideration, the Company's Board of Directors, on May 28, 2012, unanimously (i) approved and declared advisable the merger agreement, the merger and the transactions contemplated by the merger agreement, (ii) declared that it is in the best interests of the stockholders of the Company that the Company enter into the merger agreement and consummate the merger on the terms and subject to the conditions set forth in the merger agreement, (iii) directed that the adoption of the merger agreement be submitted to a vote at a meeting of the stockholders of the Company and (iv) recommended to the stockholders of the Company that they vote "FOR" the adoption of the merger agreement.

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        In reaching its determination, the members of the Company's Board of Directors consulted with the Company's management, as well as the Company's outside financial and legal advisors, considered the short-term and long-term interests and prospects of the Company and its stockholders, and considered a number of factors, including, among others, the following:

•

the Company's historical and current financial performance and results of operations, the Company's prospects and long-term strategy, the Company's competitive position and general economic and stock market conditions;



•

the Company's Board of Directors knowledge of the Company's businesses, assets, financial condition, results of operations and prospects (as well as the risks involved in achieving those prospects), the nature of the Company's businesses and the industries in which the Company competes and the market for Interline common stock;



•

the Company's financial and strategic plan and the initiatives and the potential execution risks associated with such plan, and the effects of the economy on the Company specifically, and on the Company's industries generally, and in connection with these considerations, the attendant risk that, if the Company did not enter into the merger agreement, the price that might be received by the Company's stockholders selling stock of the Company in the open market, both from a short-term and long-term perspective, could be less than the merger consideration;



•

the current condition of the financial markets, including the availability of committed financing (subject to limited restrictions) for the merger, and the risk, in the future, of deterioration in such conditions;



•

the historical market prices of Interline common stock and recent trading activity, including the fact that the merger consideration represents a premium of approximately 42% relative to the Company's closing stock price on May 25, 2012, the last trading day before the announcement of the transaction, and 31% relative to the Company's trailing 30-day average closing stock price for the period ended on May 25, 2012;



•

the Company's Board of Directors belief, based on the factors described above, that the $25.50 in cash per share merger consideration would result in greater value to the Company's stockholders than the available alternatives;



•

the fact that the consideration offered by Party A and Party B, the only two other parties with serious and continued interest in acquiring the Company, was significantly lower than $25.50 in cash per share;



•

the fact that, prior to entering into the merger agreement, a calculated canvas of certain strategic parties in the Company's operating space failed to yield serious interest among those strategic parties with regard to a potential acquisition of the Company;



•

the fact that the consideration to be paid pursuant to the merger agreement would be all cash, which would provide certainty and immediate value to the Company's stockholders, including because stockholders will not be exposed to the risks and uncertainties relating to the Company's prospects;



•

the oral opinion of Barclays rendered on May 28, 2012, which opinion was subsequently confirmed in a written opinion dated May 29, 2012, to the Company's Board of Directors to the effect that, as of that date and based upon and subject to the qualifications, limitations and assumptions stated in its written opinion, the per share merger consideration of $25.50 to be offered to the stockholders of the Company in the merger was fair, from a financial point of view, to such stockholders (other than P2 Capital Partners, LLC and its affiliated funds). The full text of the written opinion of Barclays, dated May 29, 2012, which sets forth, among other things, the assumptions made, procedures followed, factors considered, and limitations upon the review undertaken by Barclays in

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rendering its opinion, is attached as Appendix C to this Proxy Statement. See "The Merger (Proposal 1)—Opinion of the Company's Financial Advisor" beginning on 38;

•

the fact that the consideration and negotiation of the merger agreement was conducted through arm's-length negotiations under the oversight of the Company's Board of Directors;



•

the terms of the merger agreement, including the fact that the merger agreement contains provisions that are designed to ensure that the $25.50 in cash per share price to be provided pursuant to the merger agreement is the best reasonably available to the Company's stockholders, including the right, subject to certain conditions, to solicit offers with respect to alternative acquisition proposals during the go-shop period, to respond to unsolicited acquisition proposals and to terminate the merger agreement and accept a "superior proposal" prior to adoption of the merger agreement, subject to payment of a termination fee of $29.9 million plus reimbursable expenses up to a maximum of $5 million (or $13.9 million plus reimbursable expenses up to a maximum of $5 million if the termination in any such circumstances is in connection with a superior proposal arising during the go-shop period and entered into prior to the cut-off date), which the Company's Board of Directors believed would not likely be a meaningful deterrent to such a superior proposal;



•

the view of the Company's Board of Directors that, given the due diligence that Parent had completed and the commitments Parent and Merger Sub had from their financing sources, Parent could successfully consummate an acquisition of the Company in a timely manner;



•

the limited number and nature of the conditions to funding set forth in the debt commitment letter and the obligation of Parent and Merger Sub to use their reasonable best efforts to obtain at the completion of the merger the financing on the terms and conditions described in the debt commitment letter (including the flex provisions in the debt facility fee letter) or alternative financing from the same or other sources of financing on terms and conditions (including the flex provisions in the debt facility fee letter) not less favorable to Parent and Merger Sub than those contained in the debt commitment letter and in an amount sufficient to timely consummate the transactions contemplated by the merger agreement on the terms and conditions set forth therein;



•

the likelihood that the merger will be completed, including the fact that conditions to closing the merger are limited to Interline stockholder approval, receipt of regulatory approvals, the Company not having suffered a material adverse effect, the Company and its domestic subsidiaries having unrestricted cash available as of the closing of the merger of at least $50 million, the accuracy of the representation and warranty with regard to the ability as of May 29, 2012 of Interline New Jersey to make restricted payments in compliance with the indenture governing the Existing Notes in an amount of not less than $200 million and other customary closing conditions, and the likelihood that the regulatory and stockholder approvals necessary to complete the merger will be obtained;



•

the fact that under certain specified circumstances Parent will be required to pay the Company a reverse termination fee equal to $51.3 million upon termination of the merger agreement, and if Parent has committed a willful and material breach of any of its representations, warranties, covenants or agreements under the merger agreement, a reverse termination fee of $68.4 million in the event of such termination;



•

the fact that the Company is contractually entitled to require GS Fund VI and the P2 Fund to perform under the limited guarantees under certain circumstances; and



•

the fact that the Company's stockholders have the right to demand appraisal of their shares in accordance with the procedures of Section 262 of the DGCL.

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        The Company's Board of Directors also considered the following adverse factors associated with the merger, among others:

•

other than with respect to P2 Capital Partners, LLC and its affiliates and certain officers and directors of the Company (discussed below), the fact that the Company's stockholders will have no ongoing equity participation in the surviving corporation following the merger, meaning that the Company's stockholders will cease to participate in the Company's future earnings or growth, or to benefit from any increases in the value of the Interline's common stock;



•

the restrictions on the conduct of the Company's business prior to the completion of the merger, including the inability of the Company to pursue certain acquisitions without the prior consent of Parent, which could delay or prevent the Company from undertaking business opportunities that may arise or certain other action the Company might otherwise take with respect to the operations of the Company pending completion of the merger;



•

that the sale of shares in the proposed merger will be a taxable transaction to the Company's stockholders;



•

that if the merger is not completed under certain circumstances, the Company will incur fees and expenses associated with the transaction that will not be reimbursed to the Company by Parent;



•

the fact that, under certain circumstances, the Company may be required to pay Parent a termination fee in an amount equal to $29.9 million plus reimbursable expenses up to a maximum of $5 million, and the effect it may have on a potential buyer considering a competing proposal to acquire the Company (or $13.9 million plus reimbursable expenses up to a maximum of $5 million if the termination in any such circumstances is in connection with a superior proposal arising during the go-shop period and entered into prior to the cut-off date);



•

the fact that, while the merger is expected to be completed, there is no assurance that all conditions to the parties' obligations to complete the merger will be satisfied or waived, and, as a result, it is possible that the merger might not be completed even if it is approved by the Company's stockholders;



•

the risk that the debt financing contemplated by the debt commitment letter or the equity financing contemplated by the equity commitment letter for the consummation of the merger might not be obtained;



•

the risks, costs and disruptions to the Company's operations if the merger is not completed, including the diversion of management and employee attention, potential employee attrition, the potential effect on the Company's business and its relationships and the likely negative effect on the trading price of Interline common stock; and



•

that certain directors and executive officers of the Company have interests in the merger that are different from, or in addition to, the Company's stockholders. See section entitled "The Merger (Proposal 1)—Interests of the Company's Directors and Executive Officers in the Merger" beginning on page 54 and "Advisory Vote on Golden Parachute Compensation (Proposal 2)" beginning on page 96.

        In reaching the determination described above, the Company's Board of Directors passed unanimous resolutions:

•

approving and declaring advisable the merger agreement, the merger and the transactions contemplated by the merger agreement;



•

declaring that it is in the best interests of the stockholders of the Company that the Company enter into the merger agreement and consummate the merger on the terms and subject to the conditions set forth in the merger agreement;

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•

directing that the adoption of the merger agreement be submitted to a vote at a meeting of the stockholders of the Company; and



•

recommending to the stockholders of the Company that they vote "FOR" the adoption of the merger agreement.

        The foregoing discussion of the information and factors considered by the Company's Board of Directors is not intended to be exhaustive but, the Company believes, includes all material factors considered by the Company's Board of Directors. In view of the wide variety of factors considered and the complexity of these matters, the Company's Board of Directors found it impracticable to, and did not, quantify or otherwise attempt to assign relative weight to each of the specific factors considered in reaching its determination. Rather, the Company's Board of Directors based its judgment on the total mix of information available to it regarding the overall effect of the merger on the Company's stockholders compared to the overall effect of any alternative transaction. Accordingly, the judgments of individual directors may have been influenced to a greater or lesser degree by their individual views with respect to different factors.

        The Company's Board of Directors has unanimously approved and declared advisable the merger agreement, and recommends that you vote "FOR" adoption of the merger agreement.

Purpose and Reasons for the Merger

        The Company's purpose for engaging in the merger is to enable its stockholders to receive $25.50 per share in cash, without interest and less any applicable withholding taxes, which represents a premium of approximately 42% relative to the Company's closing stock price on May 25, 2012, the last trading day before the announcement of the transaction, and 31% relative to the Company's trailing 30-day average closing stock price for the period ended on May 25, 2012. The Company has determined to undertake the merger at this time based on the conclusions, determinations and reasons of the Company's Board of Directors described in detail above under "The Merger (Proposal 1)—Background of the Merger" beginning on page 26 and "The Merger (Proposal 1)—Recommendation of the Company's Board of Directors" beginning on page 34.

Opinion of the Company's Financial Advisor

        The Company engaged Barclays to act as its financial advisor, including with respect to the merger. On May 28, 2012, Barclays rendered its oral opinion, which opinion was subsequently confirmed in a written opinion dated May 29, 2012, to the Company's Board of Directors to the effect that, as of that date and based upon and subject to the qualifications, limitations and assumptions stated in its written opinion, the per share merger consideration of $25.50 to be offered to the stockholders of the Company in the merger was fair, from a financial point of view, to such stockholders (other than P2 Capital Partners, LLC and its affiliated funds).

        The full text of Barclays' written opinion, dated as of May 29, 2012, is attached as Appendix C to this Proxy Statement. Barclays' written opinion sets forth, among other things, the assumptions made, procedures followed, factors considered and limitations upon the review undertaken by Barclays in rendering its opinion. The Company encourages you to read the opinion carefully in its entirety. The following is a summary of Barclays' opinion and the methodology that Barclays used to render its opinion. This summary is qualified in its entirety by reference to the full text of the opinion.

        Barclays' opinion, the issuance of which was approved by Barclays' Fairness Opinion Committee, is addressed to the Company's Board of Directors, addresses only the fairness, from a financial point of view, of the per share merger consideration to be offered to the stockholders of the Company (other than P2 Capital Partners, LLC and its affiliated funds) and does not constitute a recommendation to any stockholder of the Company as to how such stockholder should vote with respect to the merger or any

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other matter. The terms of the merger were determined through arm's-length negotiations between the Company and Parent and were unanimously approved by the Company's Board of Directors. Barclays did not recommend any specific form of consideration to the Company or that any specific form of consideration constituted the only appropriate consideration for the merger. Barclays was not requested to opine as to, and its opinion does not in any manner address, the Company's underlying business decision to proceed with or effect the merger or the likelihood of consummation of the merger. In addition, Barclays expressed no opinion on, and its opinion does not in any manner address, the fairness of the amount or the nature of any compensation to any officers, directors or employees of any parties to the merger, or any class of such persons, relative to the per share merger consideration to be offered to the stockholders of the Company in the merger. No limitations were imposed by the Company's Board of Directors upon Barclays with respect to the investigations made or procedures followed by it in rendering its opinion.

        In arriving at its opinion, Barclays:

•

reviewed and analyzed the merger agreement and the specific terms of the merger;



•

reviewed and analyzed publicly available information concerning the Company that Barclays believed to be relevant to its analysis, including the Company's Annual Report on Form 10-K for the fiscal year ended December 30, 2011 and Quarterly Report on Form 10-Q for the fiscal quarter ended March 30, 2012;



•

reviewed and analyzed financial and operating information with respect to the business, operations and prospects of the Company furnished to Barclays by the Company, including financial projections of the Company prepared by management of the Company;



•

reviewed and analyzed a trading history of the Interline common stock from December 16, 2004 through May 25, 2012;



•

reviewed and analyzed a comparison of the historical financial results and present financial condition of the Company with those of other companies that Barclays deemed relevant;



•

reviewed and analyzed a comparison of the financial terms of the merger with the financial terms of certain other transactions that Barclays deemed relevant;



•

reviewed and analyzed estimates of independent research analysts with respect to the future financial performance of the Company;



•

had discussions with the management of the Company concerning its business, operations, assets, liabilities, financial condition and prospects; and



•

undertook such other studies, analyses and investigations as Barclays deemed appropriate.

        In arriving at its opinion, Barclays assumed and relied upon the accuracy and completeness of the financial and other information used by Barclays without any independent verification of such information (and did not assume responsibility or liability for any independent verification of such information). Barclays further relied upon the assurances of the management of the Company that they were not aware of any facts or circumstances that would make such information inaccurate or misleading. With respect to the financial projections of the Company, upon the advice of the Company, Barclays assumed that such projections were reasonably prepared on a basis reflecting the best currently available estimates and judgments of the management of the Company as to the future financial performance of the Company and that the Company would perform substantially in accordance with such projections. Barclays assumed no responsibility for and expressed no view as to any such projections or estimates or the assumptions on which they were based. In arriving at its opinion, Barclays did not conduct a physical inspection of the properties and facilities of the Company and did not make or obtain any evaluations or appraisals of the assets or liabilities of the Company. Barclays was requested to solicit third party indications of interest in the possible acquisition of all or a part of the Company's business for the go-shop period. Barclays' opinion

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was necessarily based upon market, economic and other conditions as they existed on, and could be evaluated as of, May 29, 2012. Barclays assumed no responsibility for updating or revising its opinion based on events or circumstances that may have occurred after, May 29, 2012.

        Barclays assumed the accuracy of the representations and warranties contained in the merger agreement and all agreements related thereto. Barclays also assumed, upon the advice of the Company, that all material governmental, regulatory and third party approvals, consents and releases for the merger will be obtained within the constraints contemplated by the merger agreement and that the merger will be consummated in accordance with the terms of the merger agreement without waiver, modification or amendment of any material term, condition or agreement thereof. Barclays did not express any opinion as to any tax or other consequences that might result from the merger, nor did Barclays' opinion address any legal, tax, regulatory or accounting matters, as to which Barclays understands that the Company has obtained such advice as it deemed necessary from qualified professionals.

        In connection with rendering its opinion, Barclays performed certain financial, comparative and other analyses as summarized below. In arriving at its opinion, Barclays did not ascribe a specific range of values to the shares of the Interline common stock but rather made its determination as to fairness, from a financial point of view, to the Company's stockholders of the consideration to be offered to such stockholders in the merger on the basis of various financial and comparative analyses. The preparation of a fairness opinion is a complex process and involves various determinations as to the most appropriate and relevant methods of financial and comparative analyses and the application of those methods to the particular circumstances. Therefore, a fairness opinion is not readily susceptible to summary description.

        In arriving at its opinion, Barclays did not attribute any particular weight to any single analysis or factor considered by it but rather made qualitative judgments as to the significance and relevance of each analysis and factor relative to all other analyses and factors performed and considered by it and in the context of the circumstances of the particular transaction. Accordingly, Barclays believes that its analyses must be considered as a whole, as considering any portion of such analyses and factors, without considering all analyses and factors as a whole, could create a misleading or incomplete view of the process underlying its opinion.

        The following is a summary of the material financial analyses used by Barclays in preparing its opinion to the Company's Board of Directors. Certain financial analyses summarized below include information presented in tabular format. In order to fully understand the financial analyses used by Barclays, the tables must be read together with the text of each summary, as the tables alone do not constitute a complete description of the financial analyses. In performing its analyses, Barclays made numerous assumptions with respect to industry performance, general business and economic conditions and other matters, many of which are beyond the control of the Company or any other parties to the merger. None of the Company, Parent, Merger Sub, Barclays or any other person assumes responsibility if future results are materially different from those discussed. Any estimates contained in these analyses are not necessarily indicative of actual values or predictive of future results or values, which may be significantly more or less favorable than as set forth below. In addition, analyses relating to the value of the businesses do not purport to be appraisals or reflect the prices at which the businesses may actually be sold.

Analysis of Implied Premiums and Multiples

        Barclays analyzed the implied premiums based on the per share merger consideration of $25.50 as compared to the following:

•

the closing price of the Interline common stock on May 25, 2012;



•

the average closing price of the Interline common stock for the 30-calendar day period, 60-calendar day period and 90-calendar day period ended on May 25, 2012;

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•

each of the 52-week high and 52-week low closing prices of the Interline common stock, in each case, ending on May 25, 2012; and



•

the all-time high of the Interline common stock, which occurred on August 13, 2007.

        The results of this analysis are summarized in the following table:

        Barclays also analyzed the implied multiple of the Company's enterprise value (or short- and long-term debt plus market value of common equity, minus cash and cash equivalents) to net income plus interest expense (income), net (gain) loss on extinguishment of debt, income taxes and depreciation and amortization, or Adjusted EBITDA, based on the per share merger consideration of $25.50. For purposes of its analyses, Barclays used the Company balance sheet information, last twelve month, or LTM, Adjusted EBITDA as of March 31, 2012 and estimated Adjusted EBITDA for calendar years 2012 and 2013 based on the Company's financial projections prepared by the management of the Company which assumed that the Company operates on a stand-alone, organic basis without external acquisitions (the "Organic Growth Projections"). Barclays also calculated the implied historical and projected earnings per share multiples (commonly referred to as a price earnings ratio, or P/E) based on the per share merger consideration of $25.50, with the projected earnings per share multiples based on the I/B/E/S Consensus Forecasts. The results of this analysis are summarized below:

Selected Comparable Company Analysis

        In order to assess how the public market values shares of similar publicly traded companies, Barclays reviewed and compared specific financial and operating data relating to the Company with selected companies in the distribution industry that Barclays, based on its experience in this industry, deemed comparable to the Company. The selected comparable companies were:

Industrial End-Market Companies

Airgas, Inc.
Anixter International Inc.
Applied Industrial Technologies, Inc.
Barnes Group Inc.

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Dorman Products, Inc.
Fastenal Company
Genuine Parts Company
Houston Wire & Cable Company
Kaman Corporation
MSC Industrial Direct Co., Inc.
Rexel S.A.
WESCO International, Inc.
W.W. Grainger, Inc.

Residential End-Market Companies

Beacon Roofing Supply, Inc.
Pool Corporation
Universal Forest Products, Inc.
Watsco, Inc.
Wolseley PLC

        Barclays calculated and compared various financial multiples and ratios of the Company and the selected comparable companies. As part of its selected comparable company analysis, Barclays calculated, among other things, the ratio of each company's enterprise value to historical and projected earnings before interest, taxes, depreciation and amortization, or EBITDA. The enterprise value of each company was obtained by adding its short and long-term debt to the sum of the market value of its common equity, the value of any preferred stock (at liquidation value) and the book value of any minority interest, and subtracting its cash and cash equivalents. All of these calculations were performed, and based on publicly available financial data (including FactSet and I/B/E/S Consensus) and closing prices, as of May 25, 2012, the last trading date prior to the delivery of Barclays' opinion. The results of this selected comparable company analysis are summarized below:

Enterprise Value as a Multiple of Calendar Year 2012 Estimated EBITDA

        Barclays selected the comparable companies listed above because of similarities in one or more business or operating characteristics with the Company. However, because of the inherent differences between the business, operations and prospects of the Company and those of the selected comparable companies, and because no selected comparable company is exactly the same as the Company, Barclays believed that it was inappropriate to, and therefore did not, rely solely on the quantitative results of the selected comparable company analysis. Accordingly, Barclays also made qualitative judgments concerning differences between the business, financial and operating characteristics and prospects of the Company and the selected comparable companies that could affect the public trading values of each in order to provide a context in which to consider the results of the quantitative analysis. These qualitative judgments related primarily to the differing sizes, growth prospects, profitability levels and degree of operational risk between the Company and the companies included in the selected company analysis. Based upon these judgments, Barclays selected a range of 6.5x to 8.5x calendar year 2012 estimated Adjusted EBITDA for the Company and applied such range to the Organic Growth Projections to calculate a range of implied prices per share of the Company. The selected comparable company analysis yielded an implied valuation range for the Interline common stock of $16.00 to $23.00 per share (per share values were rounded to the nearest $0.50 increment), compared to the per share merger consideration of $25.50.

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Selected Precedent Transaction Analysis

        Barclays reviewed and compared the purchase prices and financial multiples paid in selected other transactions that Barclays, based on its experience with merger and acquisition transactions, deemed relevant. Barclays chose such transactions based on, among other things, the similarity of the applicable target companies in the transactions to the Company with respect to the size, mix, margins and other characteristics of their businesses. The following tables set forth the transactions analyzed based on such characteristics and the results of such analysis:

Enterprise Value as a Multiple of LTM EBITDA

        The reasons for and the circumstances surrounding each of the selected precedent transactions analyzed were diverse and there are inherent differences in the business, operations, financial conditions

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and prospects of the Company and the companies included in the selected precedent transaction analysis. Accordingly, Barclays believed that a purely quantitative selected precedent transaction analysis would not be particularly meaningful in the context of considering the merger. Barclays therefore made qualitative judgments concerning differences between the characteristics of the selected precedent transactions and the merger which would affect the acquisition values of the selected target companies and the Company. Based upon these judgments, Barclays selected a range of 8.5x to 10.5x LTM Adjusted EBITDA and applied such range to the LTM Adjusted EBITDA (as of March 31, 2012) of the Company to calculate a range of implied prices per share of the Company. The selected precedent transactions analysis yielded an implied valuation range for the Interline common stock of $22.00 to $28.00 per share (per share values were rounded to the nearest $0.50 increment), compared to the per share merger consideration of $25.50.

Discounted Cash Flow Analysis

        In order to estimate the present value of the Interline common stock, Barclays performed a discounted cash flow analysis of the Company. A discounted cash flow analysis is a traditional valuation methodology used to derive a valuation of an asset by calculating the "present value" of estimated future cash flows of the asset. "Present value" refers to the current value of future cash flows or amounts and is obtained by discounting those future cash flows or amounts by a discount rate that takes into account macroeconomic assumptions and estimates of risk, the opportunity cost of capital, expected returns and other appropriate factors.

        To calculate the estimated enterprise value of the Company using the discounted cash flow method, Barclays added (i) the total present value of the Company's projected after-tax unlevered free cash flows for March 31, 2012 through December 31, 2016 based on two management projections cases, the Organic Growth Projections and another set of projections which assume that the Company achieves growth through both organic means and through acquisitions (the "Organic and Acquisitions Growth Projections"), to (ii) the present value of the Company's "terminal value" as of December 31, 2016. The after-tax unlevered free cash flows were calculated by taking the tax-affected earnings before interest, tax expense and amortization (excluding amortization of purchased intangibles) and adding back depreciation, subtracting capital expenditures and adjusting for changes in net working capital (including a provision for doubtful accounts). The residual value of the Company at the end of the forecast period, or "terminal value," was estimated by selecting a range of terminal value multiples based on estimated Adjusted EBITDA for the period ending December 31, 2017 of 6.5x to 8.5x, which was derived by analyzing the results from the selected comparable company analysis and applying such range to the Organic Growth Projections and the Organic and Acquisitions Growth Projections. The range of after-tax discount rates of 10.5% to 12.5% was selected based on an analysis of the weighted average cost of capital of the comparable companies.

        Combining the total present value of the estimated unlevered free cash flows and the present value of the terminal values resulted in a range of implied enterprise values for the Company. Barclays then deducted outstanding net debt in the assumed amount of approximately $225 million to determine a range of implied equity values of the Company. The discounted cash flow analysis yielded an implied valuation range for the Interline common stock of $22.50 to $31.50 per share based on the Organic Growth Projections, and $23.50 to $34.00 based on the Organic and Acquisitions Growth Projections (per share values were rounded to the nearest $0.50 increment), in each case, compared to the per share merger consideration of $25.50.

Analyst Price Targets

        Barclays reviewed the public market trading price targets for the Interline common stock prepared and published by securities research analysts as of May 25, 2012. These targets reflected each analyst's estimate of the future public market trading price for the Interline common stock. The public market trading price targets published by securities research analysts do not necessarily reflect current market

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trading prices for the shares and these estimates are subject to uncertainties, including future financial performance of the Company and future financial market conditions. The equity analysts price targets for the Interline common stock were both $25.00 per share, compared to the per share merger consideration of $25.50.

Transaction Premium Analysis

        In order to assess the premium offered to the stockholders of the Company in the merger relative to the premiums offered to stockholders in other transactions, Barclays reviewed the premium paid in selected cash consideration transactions of companies valued between $500 million and $2 billion from May 1, 2002 to May 1, 2012. For each transaction, Barclays calculated the premium per share paid by the acquirer by comparing the announced transaction value per share to the target company's historical average share price during the following periods: (i) one trading day prior to announcement, (ii) 1 week prior to announcement and (iii) 4 weeks prior to announcement. The results of this transaction premium analysis are summarized below:

        The reasons for and the circumstances surrounding each of the transactions analyzed in the transaction premium analysis were diverse and there are inherent differences in the business, operations, financial conditions and prospects of the Company and the companies included in the transaction premium analysis. Accordingly, Barclays believed that a purely quantitative transaction premium analysis would not be particularly meaningful in the context of considering the merger. Barclays therefore made qualitative judgments concerning the differences between the characteristics of the selected transactions and the merger which would affect the acquisition values of the target companies and the Company. Based upon these judgments, Barclays selected a range of 30% to 40% to the closing price of the Interline common stock on May 25, 2012 to calculate a range of implied prices per share of the Company. The transaction premium analysis yielded an implied valuation range for the Interline common stock of $23.00 to $25.00 per share (per share values were rounded to the nearest $0.50 increment), compared to the per share merger consideration of $25.50.

Leveraged Acquisition Analysis

        Barclays performed a leveraged acquisition analysis in order to ascertain a price for the Interline common stock that might be achieved in a leveraged buyout transaction with a financial buyer assuming two different structures, an "Operating Company Debt Structure", which assumes the Company's existing capital structure is refinanced resulting in "breakage" costs on outstanding bonds of approximately $41.3 million, and a "Holding Company Debt Structure", which assumes no breakage costs and is the debt capital structure consistent with the merger. Barclays assumed the following in its analysis: (i) a debt capital structure of the Company comprised of total leverage of funded debt to Adjusted EBITDA as of March 31, 2012 of approximately 6.0x, (ii) an equity investment that would achieve a rate of return in the low 20% range over approximately five years, and (iii) a projected Adjusted EBITDA terminal value multiple of 8.5x to 9.5x LTM Adjusted EBITDA. Based upon these assumptions, Barclays calculated a range of implied enterprise values for the Company. Barclays then deducted outstanding debt and added outstanding cash and equivalents to determine a range of implied equity values of the Company. The leveraged acquisition analysis yielded an implied valuation range for the Interline common stock of $24.00 to $26.00 per share based on the Holding Company Debt Structure, and $23.00 to $25.00 based on the

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Operating Company Debt Structure (per share values were rounded to the nearest $0.50 increment), in each case, compared to the per share merger consideration of $25.50.

General

        Barclays is an internationally recognized investment banking firm and, as part of its investment banking activities, is regularly engaged in the valuation of businesses and their securities in connection with mergers and acquisitions, investments for passive and control purposes, negotiated underwritings, competitive bids, secondary distributions of listed and unlisted securities, private placements and valuations for estate, corporate and other purposes. the Company's Board of Directors selected Barclays because of its familiarity with the Company and its qualifications, reputation and experience in the valuation of businesses and securities in connection with mergers and acquisitions generally, as well as substantial experience in transactions comparable to the merger.

        Barclays is acting as financial advisor to the Company in connection with the merger, including in connection with the "go-shop". As compensation for its services in connection with the merger, an opinion fee of $500,000 became payable to Barclays upon the delivery of Barclays' opinion. Additional compensation of approximately $11.4 million will be payable on completion of the merger. In addition, the Company has agreed to reimburse Barclays for a portion of its reasonable out-of-pocket expenses incurred in connection with the merger and to indemnify Barclays for certain liabilities that may arise out of its engagement by the Company and the rendering of Barclays' opinion. Barclays has performed various investment banking and financial services for the Company in the past, and expects to perform such services in the future, and has received, and is likely to receive, customary fees for such services. Specifically, in the past two years, Barclays has performed the following investment banking and financial services: (i) Joint Lead Arranger and Bookrunner on the Company's $225 million ABL Revolving Credit Facility, (ii) Lead Dealer Manager on the Company's $150 million debt tender offer and (iii) Lead Bookrunner on the Company's $300 million Senior Subordinated Notes offering. In addition, Barclays and its affiliates in the past have provided, currently are providing, or in the future may provide, investment banking and other financial services to GS Capital Partners which, following the closing of the transactions contemplated by the merger agreement, together with one or more investment funds managed by P2 Capital Partners, LLC is a parent company of Parent, and certain of GS Capital Partners' affiliates and portfolio companies and have received or in the future may receive customary fees for rendering such services, including (i) having acted or acting as financial advisor to GS Capital Partners and certain of its portfolio companies and affiliates in connection with certain mergers and acquisition transactions, (ii) having acted or acting as arranger, bookrunner and/or lender for GS Capital Partners and certain of its portfolio companies and affiliates in connection with the financing for various acquisition transactions and (iii) having acted or acting as underwriter, initial purchaser and placement agent for various equity and debt offerings undertaken by GS Capital Partners and certain of its portfolio companies and affiliates. In addition, Barclays and its affiliates in the future may provide or seek to provide investment banking and other financial services to P2 Capital Partners, LLC and its affiliated entities and/or funds for which Barclays would expect to receive customary fees.

        Barclays and its affiliates engage in a wide range of businesses from investment and commercial banking, lending, asset management and other financial and non-financial services. In the ordinary course of its business, Barclays and affiliates may actively trade and effect transactions in the equity, debt and/or other securities (and any derivatives thereof) and financial instruments (including loans and other obligations) of (i) the Company, (ii) GS Capital Partners and certain of GS Capital Partners' affiliated entities and/or funds, and (iii) P2 Capital Partners, LLC and certain of P2 Capital Partners, LLC's affiliated entities and/or funds, for its own account and for the accounts of its customers and, accordingly, may at any time hold long or short positions and investments in such securities and financial instruments.

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Projected Financial Information

        In connection with GS Capital Partners' and P2 Capital Partners, LLC's due diligence review, the Company provided to GS Capital Partners and P2 Capital Partners, LLC certain projected financial information concerning the Company prepared by the Company's management. Set forth below are selected summaries of the material projected financial information provided to GS Capital Partners and P2 Capital Partners, LLC on March 23, 2012 (the "March Projections") and projected free cash flow information provided to GS Capital Partners and P2 Capital Partners, LLC in the electronic dataroom on April 9, 2012 (the "Cash Flow Projections" and together with the March Projections, the "Projections"), in each case, which includes two separate sets of projections, (i) one of which, the Organic Growth Projections, assumes the Company operates on a stand-alone, organic basis without acquisitions and (ii) the other of which, the Organic and Acquisitions Growth Projections, assumes the Company achieves growth through both organic means and through acquisitions. The inclusion of the Projections in this Proxy Statement should not be regarded as an admission or representation of Interline, GS Capital Partners, P2 Capital Partners, LLC, Parent or Merger Sub, or an indication that any of Interline, GS Capital Partners, P2 Capital Partners, LLC, Parent or Merger Sub or their respective affiliates or representatives considered, or now consider, the Projections to be a reliable prediction of actual future events or results, and the Projections should not be relied upon as such. The Projections are being provided in this document only because Interline made them available to GS Capital Partners and P2 Capital Partners, LLC in connection with GS Capital Partners' and P2 Capital Partners, LLC's due diligence review of Interline and also to Barclays in connection with its engagement as financial advisor to the Company's Board of Directors. None of Interline, GS Capital Partners, P2 Capital Partners, LLC, Parent or Merger Sub or any of their respective affiliates or representatives assumes any responsibility for the accuracy of the Projections or makes any representation to any stockholder regarding the Projections, and none of them intends to update or otherwise revise the Projections to reflect circumstances existing after the date when made or to reflect the occurrence of future events, even in the event that any or all of the assumptions underlying the Projections are shown to be in error.

        The Projections were prepared by the Company's management. The Projections were not prepared with a view to public disclosure or complying with GAAP, the published guidelines of the SEC regarding projections or the guidelines established by the American Institute of Certified Public Accountants for preparation and presentation of prospective financial information. Interline's independent registered public accounting firm has not examined, compiled or performed any procedures with respect to the Projections presented in this Proxy Statement, and it has not expressed any opinion or any other form of assurance of such information or the likelihood that Interline may achieve the results contained in the Projections, and accordingly assumes no responsibility for them and disclaims any association with them. The ultimate achievability of the Projections included herein is also subject to numerous risks and uncertainties including but not limited to the risks and uncertainties described in the Company's Annual Report on Form 10-K for the fiscal year ended December 30, 2011 and subsequent filings made with the SEC. The Company has made publicly available the Company's actual results of operations for the first quarter of fiscal year 2012. You should review the Company's Quarterly Report on Form 10-Q for the quarter ended March 30, 2012 to obtain this information. Readers of this Proxy Statement are strongly cautioned not to place undue reliance on the Projections set forth below.

        The Projections reflect numerous estimates and assumptions with respect to industry performance, general business, economic, regulatory, market and financial conditions, as well as matters specific to the Company's business. Many of these matters are beyond the Company's control and the continuing uncertainty surrounding general economic conditions and in the industry in which the Company operates creates significant uncertainty around the Projections. As a result, there can be no assurance that the projected results will be realized or that actual results will not be significantly higher or lower than projected. See also "Cautionary Statements Concerning Forward-Looking Information" beginning on page 21. Because the Projections cover multiple years, such information by its nature becomes less reliable with each successive year. The Projections do not take into account any circumstances or events occurring

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after the date they were prepared, including the announcement of the merger. There can be no assurance that the announcement of the merger will not affect the Company's business. Further, the Projections do not take into account the effect of any failure to occur of the merger and should not be viewed as accurate or continuing in that context.

        In addition, the Projections included non-GAAP financial measures under SEC rules, including (i) "Adjusted EBITDA," which the Company defines as net income plus interest expense (income), net, (gain) loss on extinguishment of debt, net, income taxes and depreciation and amortization and (ii) "free cash flow" which the Company defines as net cash provided by operating activities, as defined under GAAP, less capital expenditures. The Company provided this information to GS Capital Partners, P2 Capital Partners, LLC and Barclays because the Company believed it could be useful in evaluating, on a prospective basis, the Company's potential operating performance and cash flow. This information should not be considered in isolation or in lieu of the Company's operating and other financial information determined in accordance with GAAP. In addition, because non-GAAP financial measures are not determined consistently by all entities, the non-GAAP measures presented in the Projections may not be comparable to similarly titled measures of other companies. A reconciliation of Adjusted EBITDA and free cash flow to the most directly comparable GAAP measure (net income), prepared by the Company's management, is provided below. In the reconciliation tables below, numbers may not sum exactly due to rounding.

Projected Financial Information
Management Projections (Organic Growth Projections)
($ in millions)

Reconciliation of Non-GAAP Measures
(Management Projections (Organic Growth Projections))
($ in millions)

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Projected Financial Information
Management Projections (Organic and Acquisitions Growth Projections)
($ in millions)

Reconciliation of Non-GAAP Measures
Management Projections (Organic and Acquisitions Growth Projections))
($ in millions)

Certain Effects of the Merger

        If the merger is completed, all of the equity interests in the Company will be owned by Parent. No current Company stockholder will have any ownership interest in, or be a stockholder of, the Company, except for (i) P2 Capital Partners, LLC or affiliates of P2 Capital Partners, LLC which, as of the date of the merger agreement, own shares in the Company, (ii) the Company's chief executive officer, who has agreed to reinvest $6.7 million in Parent at the time of the merger, and other members of senior management, who are expected to reinvest in Parent between 30% and 50% of their after-tax proceeds from the merger attributable to each component of their existing equity, a portion of which, in each case, may be satisfied through an exchange of shares and/or options (which in the case of options will be based on the intrinsic value of the exchanged options on the date of closing of the merger) in the Company for shares and/or options in Parent, (iii) members of senior management who may be entitled to participate in equity plans

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of the surviving corporation or its affiliates, or (iv) as otherwise provided in this Proxy Statement. As a result, the Company's stockholders will no longer benefit from any increases in the Company's value, nor will they bear the risk of any decreases in the Company's value. Following the merger, Parent will benefit from any increases in the value of the Company and also will bear the risk of any decreases in the value of the Company.

        If the merger is completed, each share of the Interline common stock owned immediately prior to the effective time of the merger, other than as provided below, will be converted into the right to receive $25.50 in cash, without interest and less any applicable withholding taxes. The following shares of the Interline common stock will not be converted into the right to receive the per share merger consideration in connection with the merger: (a) shares of common stock owned by the Company, (b) shares of common stock owned by Parent or Merger Sub, including shares contributed to Parent by the P2 Fund and certain members of Company management or (c) shares of common stock whose holders have not voted in favor of adopting the merger agreement and have demanded and perfected their appraisal rights under Section 262 of the General Corporation Law of the State of Delaware.

        If the merger is completed, each option holder will be entitled to receive the excess, if any, of the $25.50 per share merger consideration and the option excess price, regardless of whether the option is then exercisable, each restricted share unit will vest and each holder of restricted share units will be entitled to receive the maximum amount such holder is entitled to under such award, and each share of restricted stock will vest and each holder of shares of restricted stock will be entitled to receive an amount equal to $25.50 (the per share merger consideration) per share of Interline common stock underlying such share of restricted stock, in each case, without interest and less any applicable withholding taxes. As of the date of this Proxy Statement, there are no shares of restricted stock outstanding.

        If the merger is completed, the common stock will be delisted from the New York Stock Exchange (and no longer publicly traded) and deregistered under the Securities Exchange Act of 1934, as amended (the "Exchange Act"), and the Company will no longer file periodic reports with the SEC with respect to the Interline common stock, in each case, in accordance with applicable law, rule or regulation.

Effects on the Company if the Merger is Not Completed

        If the merger agreement is not approved by the Company's stockholders or if the merger is not completed for any other reason, the Company's stockholders will not receive any payment for their shares in connection with the merger. Instead, the Company will remain an independent public company, and Interline common stock will continue to be quoted on the New York Stock Exchange. In addition, if the merger is not completed, the Company expects that management will operate the Company's business in a manner similar to that in which it is being operated today and that the Company's stockholders will continue to be subject to the same risks and opportunities to which they are currently subject, including, without limitation, risks related to the highly competitive industry in which the Company operates and adverse economic conditions.

        Furthermore, if the merger is not completed, and depending on the circumstances that would have caused the merger not to be completed, it is likely that the price of Interline common stock will decline significantly. If that were to occur, it is uncertain when, if ever, the price of Interline common stock would return to the price at which it trades as of the date of this Proxy Statement.

        Accordingly, if the merger is not completed, there can be no assurance as to the effect of these risks and opportunities on the future value of your shares of Interline common stock. If the merger is not completed, the Company's Board of Directors will continue to evaluate and review the Company's business operations, properties, dividend policy and capitalization, among other things, make such changes as are deemed appropriate and continue to seek to identify strategic alternatives to enhance stockholder value. If the merger agreement is not approved by the Company's stockholders or if the merger is not completed for any other reason, there can be no assurance that any other transaction acceptable to the Company will be offered or that the Company's business, prospects or results of operation will not be adversely impacted.

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        In addition, if the merger agreement is terminated, under specified circumstances, the Company would be required to pay Parent a termination fee in an amount equal to $29.9 million plus reimbursable expenses up to a maximum of $5 million (or $13.9 million plus reimbursable expenses up to a maximum of $5 million if the termination in any such circumstances is in connection with a superior proposal arising during the go-shop period and entered into prior to the cut-off date). The merger agreement also provides that Parent will be required to pay the Company a reverse termination fee equal to $51.3 million upon termination under certain specified circumstances, and a reverse termination fee of $68.4 million in the event of termination under such circumstances if Parent has committed a willful and material breach of any of its representations, warranties, covenants or agreements under the merger agreement. See "The Merger Agreement—Effect of Termination; Fees and Expenses."

Regulatory Approvals

        In connection with the merger, the Company is required to make certain filings with, and comply with certain laws of, various federal and statement governmental agencies, including:

•

filing the certificate of merger with the Secretary of State of the State of Delaware in accordance with the DGCL after the adoption of the merger agreement by the Company's stockholders; and



•

complying with U.S. federal securities laws.

        In addition, under the HSR Act, and the related rules and regulations that have been issued by the Federal Trade Commission ("FTC"), certain transactions having a value above specified thresholds may not be consummated until specified information and documentary material have been furnished to the applicable governmental authorities and certain waiting period requirements have been satisfied. The requirements of the HSR Act apply to the acquisition of shares of the Interline common stock in the merger. Early termination of the waiting period under the HSR Act with respect to the merger was granted on June 20, 2012.

        At any time before or after consummation of the merger, notwithstanding the early termination of the waiting period under the HSR Act, the Antitrust Division of the Department of Justice the FTC or state or foreign antitrust and competition authorities could take such action under applicable antitrust laws as each deems necessary or desirable in the public interest, including seeking to enjoin the consummation of the merger or seeking divestiture of substantial assets of the Company or Parent. Private parties may also seek to take legal action under the antitrust laws under certain circumstances.

Merger Financing

        The obligations of Parent and Merger Sub to complete the merger under the merger agreement are not subject to a condition of Parent or Merger Sub obtaining funds to consummate the merger and the other transactions contemplated by the merger agreement. Parent has obtained equity commitments and Merger Sub has obtained debt financing commitments for the transactions contemplated by the merger agreement, the proceeds of which, together with cash on hand at the Company and assuming the financing commitments are funded in accordance with their terms, will be used by Parent to pay the aggregate merger consideration and all related fees and expenses, to refinance certain indebtedness of the Company and to pay any other amounts required to be paid at the closing date of the merger in connection with the consummation of the transactions contemplated by the merger agreement.

        In addition, the merger agreement requires the Company to use reasonable best efforts to commence a certain consent solicitation to the holders of the Existing Notes (as defined herein) with respect to (1) a modification of the definition of "Change of Control" in accordance with the Existing Indenture (as defined herein) as a result of which the transactions contemplated by the merger agreement will not constitute a "Change of Control" and GS Capital Partners VI, L.P. and P2 Capital Partners, LLC and each of their affiliates, and certain members of management of Interline New Jersey or a direct or indirect parent of Interline New Jersey will thereafter constitute permitted holders thereunder or (2) or as may otherwise be reasonably determined by Parent (and reasonably satisfactory to the Company) for purposes of facilitating the transactions contemplated by the merger agreement. The requisite consents being sought

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in the Consent Solicitation (the "Requisite Consents") were successfully obtained on June 27, 2012. If the Requisite Consents had not been obtained, the Company agreed to use its reasonable best efforts to commence, as promptly as practicable following receipt of written instructions from Parent, one or more offers to purchase the Existing Notes (such offers to be conditioned on the consummation of the merger), including as a change of control offer in compliance with the terms of the Existing Indenture and/or as a cash tender offer; provided that the Company is reasonably satisfied that Parent will be able to pay all required amounts and that the Offer (as defined herein) will state that consent fees, premiums, interest and principal in connection with the Offer will be paid by Parent. In addition, Parent obtained the Interline New Jersey Bridge Facility (as defined herein) for purposes of having a source of funds to finance the principal amount of any Existing Notes tendered in connection with any such Offer. See "The Merger Agreement—Certain Covenants of Each Party—Existing Notes" on page 82.

Equity Financing

        The GS Funds have committed, severally among them, to capitalize Parent, at or prior to the closing of the merger, with an aggregate equity contribution in an amount of $369,273,082, which amount may be reduced to the extent that Parent has not required the full amount of such equity commitment to consummate the transactions contemplated by the merger agreement and which amount may be reduced to the extent the P2 Fund funds the cash portion of its equity commitment, on the terms and subject to the conditions set forth in the equity commitment letter entered into by the GS Funds in connection with the merger. The equity commitment of the GS Funds is conditioned upon (i) the satisfaction or waiver of the conditions to the obligations of Parent and Merger Sub to consummate the transactions contemplated by the merger, (ii) the concurrent contribution of certain shares of common stock of Interline held by the P2 Fund, (iii) funding of the debt financing (to the extent necessary to fund a portion of the amounts payable by Parent at the closing of the merger) and (iv) the substantially concurrent consummation of the merger or the Company having confirmed to Parent that if specific performance is granted and the equity financing and debt financing are funded, then closing of the merger will occur and the Company has agreed to waive any unsatisfied conditions under the merger agreement.

        The GS Funds may assign all or a portion of its equity commitment to its affiliates or affiliated funds or to entities governed by an affiliate or an affiliated fund so long as such assignment does not relieve the GS Funds of its obligations under the equity commitment letter or would not reasonably be expected to materially impair, delay or prevent the funding of its equity commitment.

        The P2 Fund has committed to capitalize Parent, at or prior to the closing of the merger, with an equity contribution in an amount of $6,351,657 and 927,386 shares of common stock of the Company, which amount may be reduced to the extent that Parent has not required the full amount of such equity commitment to consummate the transactions contemplated by the merger agreement, on the terms and subject to the conditions set forth in the equity commitment letter entered into by the P2 Fund in connection with the merger. The equity commitment of the P2 Fund is conditioned upon (i) the satisfaction or waiver of the conditions to the obligations of Parent and Merger Sub to consummate the transactions contemplated by the merger, (ii) the concurrent contribution of the GS Funds equity commitment, (iii) funding of the debt financing (to the extent necessary to fund a portion of the amounts payable by Parent at the closing of the merger) and (iv) the substantially concurrent consummation of the merger or the Company having confirmed to Parent that if specific performance is granted and the equity financing and debt financing are funded, then closing of the merger will occur and the Company has agreed to waive any unsatisfied conditions under the merger agreement.

Debt Financing

        Parent has advised the Company that Merger Sub has obtained debt financing commitments for the transactions contemplated by the merger agreement, the proceeds of which (together with available cash at the Company and proceeds from the equity commitments) will be used by Parent to pay the aggregate merger consideration and all related fees and expenses and to refinance certain indebtedness of the Company. Parent has advised the Company that Goldman Sachs Lending Partners LLC ("GSLP") and

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Bank of America, N.A. ("Bank of America" and, collectively with GSLP, the "Lenders") have committed to provide a $250 million senior secured asset based revolving credit facility, a $303 million senior unsecured bridge facility to be entered into by Interline New Jersey (the "Interline New Jersey Bridge Facility"), and a $375 million senior unsecured holdco bridge facility (the "Holdco Bridge Facility"), on the terms and subject to the conditions set forth in a debt commitment letter dated May 29, 2012 (the "Debt Commitment Letter"). Parent has obtained the Interline New Jersey Bridge Facility for purposes of having a source of funds to finance the principal amount of any Existing Notes tendered in connection with an Offer.

        The obligation of the Lenders to provide debt financing under the Debt Commitment Letter is subject to a number of conditions, including without limitation: (i) the absence of a Company Material Adverse Effect (as defined in the Debt Commitment Letter) since December 31, 2011, (ii) execution and delivery of definitive documentation with respect to the debt financing contemplated by the Debt Commitment Letter and otherwise reasonably satisfactory to the Lenders, (iii) accuracy of certain specified representations and warranties in the loan documents and in the merger agreement, (iv) receipt of equity financing from the investors representing at least 30.0% of the pro forma capitalization of the Company after consummation of the merger, (v) certain marketing periods with respect to the financing shall have expired and (vi) consummation of the merger in accordance with the merger agreement. The final termination date for the Debt Commitment Letter is the earliest of: (i) the date on which the merger agreement is terminated in accordance with its terms prior to the consummation of the merger, (ii) the consummation of the merger with or without the funding of any of the proposed credit facilities, (iii) in the case of the Interline New Jersey Bridge Facility, the receipt of the Requisite Consents comprising the consenting vote of holders of a majority in aggregate principal amount of the existing 7.00% senior subordinated notes due 2018 (the "Existing Notes") of the Company's subsidiary Interline Brands, Inc., a New Jersey corporation, to the proposed amendments to the indenture for the Existing Notes, (iv) Parent's engagement or allowance of any person other than the Lenders to act as arranger and/or bookrunner (or otherwise to perform the duties and exercise the authority customarily performed and exercised by persons in such roles) for any amendment, modification, waiver or offer with respect to the Existing Notes, (v) in the case of the Holdco Bridge Facility prior to the date of issuance of certain permanent debt in lieu thereof, the business day following receipt by the Lenders of written notice from Parent terminating in full the Holdco Bridge Facility commitments on such date and (vi) 11:59 p.m., New York City time, on November 29, 2012.

        The Lenders' commitments to provide the debt financing are not conditioned upon a successful syndication of any of the credit facilities. Prior to the completion of the merger, no assignment, syndication or participation of the credit facilities by a Lender in respect of its commitment will relieve such Lender of its obligations under the debt commitment letter.

Limited Guarantees

        In connection with the merger agreement, GS Fund VI has executed a limited guarantee in favor of the Company to guarantee, subject to the limitations described therein, certain obligations of Parent and/or Merger Sub pursuant to the merger agreement. Under the limited guarantee, GS Fund VI has guaranteed 100% of (i) certain indemnification and reimbursement obligations under the merger agreement, (ii) the payment of any reverse termination fee that may become payable by Parent and Merger Sub following a termination of the merger agreement by the Company in specified circumstances, and (iii) all costs and expenses (including attorney's fees and expenses) reasonably incurred by the Company in connection with the enforcement of the limited guarantee or the exercise of specific performance under the merger agreement that results in a judgment against Parent, Merger Sub or GS Fund VI, subject to an overall cap of $68.4 million plus the amount of the reimbursement and indemnification obligations under the merger agreement and any costs and expenses reasonably incurred by the Company in connection with the enforcement of the limited guarantee or the exercise of specific performance under the merger agreement.

        In connection with the merger agreement, the P2 Fund has also executed a limited guarantee in favor of the Company to guarantee, subject to the limitations described therein, certain obligations of Parent

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and/or Merger Sub pursuant to the merger agreement. Under the limited guarantee, the P2 Fund has guaranteed 8.05% of (i) certain indemnification and reimbursement obligations under the merger agreement, (ii) the payment of any reverse termination fee that may become payable by Parent and Merger Sub following a termination of the merger agreement by the Company in specified circumstances, and (iii) all costs and expenses (including attorney's fees and expenses) reasonably incurred by the Company in connection with the enforcement of the limited guarantee or the exercise of specific performance under the merger agreement that results in a judgment against Parent, Merger Sub or P2 Fund, subject to an overall cap of 8.05% of $68.4 million plus the amount of the reimbursement and indemnification obligations under the merger agreement and any costs and expenses reasonably incurred by the Company in connection with the enforcement of the limited guarantee or the exercise of specific performance under the merger agreement.

        Each of the limited guarantees will terminate on the earliest of (i) the consummation of the merger, (ii) three months from the date of termination of the merger agreement in accordance with its terms under circumstances in which Parent would have no obligation to pay any termination fee and no obligation for certain reimbursement and indemnification obligations under the merger agreement, and (ii) six months from the date of termination of the merger agreement in accordance with its terms in circumstances where Parent would be obligated to pay a termination fee or Parent would be obligated to pay certain reimbursement and indemnification obligations under the merger agreement if the Company has not presented a claim in writing for payment of such obligations to either Parent, Merger Sub, or the limited guarantors by such date. Additionally, each limited guarantee will terminate in the event that the Company asserts in any litigation that the overall caps in each limited guarantee are illegal, invalid or unenforceable.

Interests of the Company's Directors and Executive Officers in the Merger

        In considering the recommendation of the Company's Board of Directors, you should be aware that some executive officers and directors of the Company have interests in the merger, including those described below and as described in "Advisory Vote on Golden Parachute Compensation (Proposal 2)" beginning on page 96 that are different from or in addition to your interests as a stockholder and that may present actual or potential conflicts of interest. The members of the Company's Board of Directors were aware of such interests and considered them, among other matters, when deciding to approve the merger and recommending that you vote "FOR" the approval of the merger agreement.

        In addition, in connection with the closing of the merger, the Company's chief executive officer has agreed to reinvest $6.7 million in Parent at the time of the merger, and it is anticipated that other members of the Company's senior management will reinvest in Parent between 30% and 50% of their after-tax proceeds from the transaction on terms to be agreed upon between management and Parent, a portion of which, in each case, may be satisfied through an exchange of shares and/or options (which in the case of options will be based on the intrinsic value of the exchanged options on the date of closing of the merger) in the Company for shares and/or options in Parent.

Indemnification of Directors and Officers; Directors' and Officers' Insurance

        Prior to the effective time of the merger, the Company will obtain and fully pay the premium for the extension of the directors' and officers' liability coverage of the Company's existing directors' and officers' insurance policies for a claims reporting or discovery period of at least six years from and after the effective time of the merger with respect to claims related to any period of time at or prior to the effective time of the merger (including in connection with the negotiation and execution of the merger agreement and the consummation of the merger). If the Company and/or the surviving corporation fail to obtain such "tail" insurance policies, Parent has agreed to cause the surviving corporation to maintain for at least six years following the effective time of the merger the current policies of directors' and officers' liability insurance or policies with terms, conditions, retentions and limits of liability which are at least as favorable with respect to claims arising out of or relating to events which occurred before or at the effective time of the merger (including in connection with the negotiation and execution of the merger agreement and the consummation of the merger). Such policies must not have an annual premium in excess of 300% of the

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annual premiums currently being paid by the Company. In addition, after the effective time, Parent and the surviving corporation has agreed to indemnify each present and former director, officer or employees of the Company or any of its subsidiaries against all costs or expenses (including reasonable attorneys' fees and expenses), judgments, fines, losses, claims, damages and liabilities in connection with any claim, charge, complaint, dispute, demand, grievance, action, litigation, audit, investigation, review, inquiry, arbitration, suit in equity or at law, administrative, regulatory or quasi-judicial proceeding, or other proceeding, including liabilities arising out of or pertaining to all acts and omissions arising out of or relating to their services as directors or officers and employees of the Company or its subsidiaries occurring prior to the effective time, whether asserted or claimed before or after the effective time. See "The Merger Agreement—Covenants of Parent and/or Merger Sub—Indemnification of Directors and Officers; Directors' and Officers' Insurance" on page 81.

Treatment of Equity-Based Awards

Options

        The merger agreement provides that immediately prior to the effective time of the merger, unless otherwise agreed upon in writing between Parent and any such holder, each stock option issued under the Company's equity compensation plans, whether or not then exercisable or vested, will be cancelled and converted into the right to receive an amount in cash equal to, without interest and less applicable withholding taxes, the product of (i) the excess of $25.50 (the per share merger consideration) over the per share exercise price of the applicable stock option and (ii) the aggregate number of shares of common stock that may be acquired upon exercise of such stock option immediately prior to the effective time of the merger.

Restricted Share Units

        The merger agreement provides that at the effective time of the merger, each restricted share unit (including deferred stock units) granted under the Company's equity compensation plans or programs will vest (to the extent not already vested) in accordance with its terms. Further, in connection with the action approving the merger and the merger agreement, the Company's Board of Directors authorized the accelerated vesting of the performance conditions applicable to restricted share units outstanding immediately prior to the consummation of the merger. Under the merger agreement, with respect to any portion of a restricted share unit award that vests based on the level of achievement of performance conditions, the number of shares of Interline common stock that vests will be equal to the maximum number of shares subject to such award. Accordingly, unless otherwise agreed upon between Parent and any such holder, all restricted share units will vest based on the maximum level of attainment of the performance conditions applicable to such award as of immediately prior to the consummation of the merger. At the effective time of the merger, unless otherwise agreed upon between Parent and any such holder, each vested restricted share unit (including deferred stock units) will be converted into the right to receive an amount in cash equal to $25.50 (the per share merger consideration) per share of Interline common stock underlying such restricted share unit, without interest and less applicable withholding taxes.

Restricted Stock

        The merger agreement provides that at the effective time of the merger, each share of restricted stock granted under the Company's equity compensation plans or programs will vest (to the extent not already vested) in accordance with its terms and each vested share of restricted stock will be converted into the right to receive an amount in cash equal to $25.50 (the per share merger consideration) per share of Interline common stock underlying such share of restricted stock, without interest and less applicable withholding taxes. As of the date of this Proxy Statement, there are no shares of restricted stock outstanding.

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Common Stock, Stock Options and Restricted Share Units to be Cashed Out in the Merger

        The following table sets forth, based on his or her beneficial ownership as of May 29, 2012, the cash proceeds that each of the Company's directors and executive officers would receive at the closing of the merger in respect of the cash-out equity-based awards (assuming for purposes of this table that no portion of any such proceeds payable to executive officers is invested in Parent, as described above):