UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 40-F

OR

For the fiscal year ended December 31, 2025

Commission file number: 001-41531

Enerflex Ltd.

(Exact name of Registrant as specified in its charter)

Suite 904, 1331 Macleod Trail S.E.

Calgary, Alberta, Canada, T2G 0K3

(403) 387-6377

(Address and telephone number of Registrant’s principal executive offices)

Enerflex Energy Systems Inc.

10815 Telge Road

Houston, Texas 77095

(281) 345-9300

(Name, address (including zip code) and telephone number (including area code) of agent for service in the United States)

Securities registered or to be registered pursuant to Section 12(b) of the Act:

Securities registered or to be registered pursuant to Section 12(g) of the Act:

None

(Title of Class)

Securities for which there is a reporting obligation pursuant to Section 15(d) of the Act:

None

(Title of Class)

For annual reports, indicate by check mark the information filed with this Form:

Indicate the number of outstanding shares of each of the issuer’s classes of capital or common stock as of the close of the period covered by the annual report.

121,801,779 Common Shares as of December 31, 2025

Indicate by check mark whether the Registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Exchange Act during the preceding 12 months (or for such shorter period that the Registrant was required to file such reports) and (2) has been subject to such filing requirements for the past 90 days. Yes ☒ No ☐

Indicate by check mark whether the registrant has submitted electronically every Interactive Data File required to be submitted pursuant to Rule 405 of Regulation S-T (§232.405 of this chapter) during the preceding 12 months (or for such shorter period that the Registrant was required to submit such files). Yes ☒ No ☐

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 12b-2 of the Exchange Act.

Emerging growth company ☐

If an emerging growth company that prepares its financial statements in accordance with U.S. GAAP, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards† provided pursuant to Section 13(a) of the Exchange Act. ☐

† The term “new or revised financial accounting standard” refers to any update issued by the Financial Accounting Standards Board to its Accounting

Standards Codification after April 5, 2012.

Indicate by check mark whether the registrant has filed a report on and attestation to its management’s assessment of the effectiveness of its internal control over financial reporting under Section 404(b) of the Sarbanes-Oxley Act (15 U.S.C. 7262(b)) by the registered public accounting firm that prepared or issued its audit report. ☒

If securities are registered pursuant to Section 12(b) of the Act, indicate by check mark whether the financial statements of the registrant included in the filing reflect the correction of an error to previously issued financial statements. ☐

Indicate by check mark whether any of those error corrections are restatements that required a recovery analysis of incentive-based compensation received by any of the registrant’s executive officers during the relevant recovery period pursuant to §240.10D-1(b).☐

EXPLANATORY NOTE

Enerflex Ltd. (“Enerflex” or the “Company”) is a Canadian issuer eligible to file its annual report pursuant to Section 13 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), on Form 40-F pursuant to the multi-jurisdictional disclosure system of the Exchange Act. The Company is a “foreign private issuer” as defined in Rule 405 under the Securities Act of 1933, as amended. Equity securities of the Company are accordingly exempt from Sections 14(a), 14(b), 14(c), 14(f) and 16 of the Exchange Act pursuant to Rule 3a12-3.

FORWARD LOOKING INFORMATION

This Annual Report on Form 40-F and the exhibits attached hereto (the “Form 40-F”) contains “forward-looking information” within the meaning of applicable Canadian securities laws and “forward-looking statements” (and together with “forward-looking information”, “FLI”) within the meaning of the safe harbor provisions of the US Private Securities Litigation Reform Act of 1995. FLI relates to Management’s expectations about future events, results of operations, and the future performance (both financial and operational) and business prospects of Enerflex. All statements other than statements of historical fact are FLI. FLI may contain, but is not limited to, words such as “anticipate”, “future”, “create”, “continue”, “expect”, “intend”, “propose”, “might”, “may”, “will”, “generate”, “should”, “could”, “would”, “believe”, “predict”, “forecast”, “future”, “opportunity”, “pursue”, “potential”, “objective”, “focus”, “endeavor”, “commit”, “target”, “growth”, or “ensure”, or the inverse of such terms or similar expressions suggesting future conditions, events, or expectations. In particular, this Form 40-F includes (without limitation) FLI pertaining to: the Company being well-positioned to serve client partners in core markets, enhancing long-term stakeholder value through sustainable improvements in efficiency, profitability, and cash flow generation, and the timing associated therewith; the anticipated completion of the divestiture of a majority of the Company's operations in the Asia Pacific ("APAC") region (the "APAC Divestiture"), and the timing thereof, if at all; expectations that Enerflex will be able to continue to deliver Engineered Systems solutions in APAC following the APAC Divestiture; the changing and evolving customer needs and expectations and the ability of the Company to adapt thereto; expectations regarding the Energy Infrastructure and After-Market Services product lines and Enerflex’s ability to build an increasingly resilient and sustainable business, stabilizing cash flows over the long term and reducing cyclicality in the business, and the timing associated therewith; increasing domestic demand and a growing liquified natural gas export industry in North America and the ability of the Company to benefit therefrom; the ability of the Company to increase its market share, including continued growth in its market share in the US Energy Infrastructure business, the strategies to achieve such growth and the timing associated therewith; expectations regarding the USA market continuing to provide the Company with opportunities to supply compression, processing, and electric power solutions; expectations regarding anticipated increases in gas egress capacity in Canada yielding opportunities for Enerflex’s Engineered Systems business; expectations as to the growth in the Latin America market and the associated opportunities for Enerflex to expand product offerings; expectations as to the growth in the Middle East and Africa market and the associated opportunities in Engineered Systems, Energy Infrastructure, and After-Market Services, and the timing associated therewith; expectations that investments in long-term infrastructure assets in the Eastern Hemisphere will grow the recurring nature of Enerflex’s business; the Company’s backlog and the ability of the Company to convert such backlog into revenue within a reasonable time frame; the Company’s backlog providing strong visibility for the Engineered Systems business; expected increases in natural gas and produced water volumes across Enerflex’s global footprint, and the timing associated therewith; the ability of the Company to continue to build strong relationships with suppliers; expectations that no aspect of the Company’s business will be materially affected by renegotiation or termination of contracts or sub-contracts; expectations that global energy demand will continue to outpace supply from new renewable capacity and that natural gas will play a critical role in the ongoing energy transition; expectations that substantially all existing and future Energy Infrastructure contracts will be extended or renewed beyond their initial terms or renewed on substantially the same commercial terms; expectations regarding compliance with existing and future laws and regulations; expectations that the Company’s quality management systems, safety systems and local emergency response plans will be effective in reducing the probability of catastrophic events that could impact human health, local communities and/or the environment; the Company's efforts to mitigate the impact of tariffs through its diversified operations and proactive risk management, and that such efforts will be successful; the partial or complete loss of certain suppliers which could result in increased costs and project delays, could have a negative impact on Enerflex’s results of operations, could damage client partner relationships, and could affect Enerflex’s competitive position; the ability of the Company to obtain and maintain prudent levels of insurance, and that such coverage will be available on commercially reasonable terms, at levels of risk coverage or policy limits that management deems adequate, or on terms as favorable as Enerflex's current arrangements; expectations that third-party service providers have adequate cyber security measures and that such security measures will prevent any cyber events or computer viruses from impacting the applications upon which Enerflex relies; efforts by the Company to hedge all significant transactional currency risks and that such efforts will be successful; the ability of the Company to successfully recover amounts owing in connection with an international Engineered Systems project in respect of which the project contract was terminated in 2024; expectations regarding future dividend payments and the ability to continue to pay such dividend; expectations regarding payments to credit rating agencies; expectations as to the timing by which the Company will file its management information circular and hold its annual general meeting of shareholders; and the Company’s belief that the historical information provided by, or derived from information provided by, third parties, is accurate.

FLI is based on assumptions, estimates and analysis made in light of the Company's experience and its perception of trends, current conditions, and expected developments, including assumptions and estimates as to associated timing and costs, as well as other factors that are believed by the Company to be reasonable and relevant in the circumstances. FLI involves known and unknown risks and uncertainties and other factors which are difficult to predict, including, without limitation: that all conditions to completion of the APAC Divestiture will be satisfied or waived in a timely manner, that all regulatory and other approvals required for completion of the APAC Divestiture will be obtained and obtained in a timely manner, that the transaction to effect the APAC Divestiture will be completed on the agreed terms, and that the expected benefits of the APAC Divestiture will be realized within the expected timeframes; the impact of general economic and industry conditions on the Company’s business, including its existing product offerings and the potential for growth and expansion of the business; stock market volatility both generally and specific to the price and liquidity of the Company’s securities; the adoption of new laws and regulations or changes to existing laws and regulations or how they are

interpreted and enforced; the adoption of new taxes and tariffs or changes to existing taxes and tariffs and how they are interpreted and enforced; force majeure events; ESG and climate change rules, regulations and policies and the interpretation and enforcement thereof; the Company’s involvement in litigation; investor sentiment toward the oil and natural gas industry and market trends within the industry; risks inherent in the Company’s supply chain and inventory management; the ability of the Company to hire and retain the personnel critical to its business; the impact to the Company’s business given adverse financial conditions of client partner(s); health, safety, and environment risks and the ability of the Company to manage such risks; increased competition and the ability of the Company to meet competitive pressures within a reasonable cost structure; volatility of oil and natural gas prices; oil and natural gas product supply and demand; future natural gas prices and natural gas exploration and development activity levels; fluctuations in interest rates and foreign exchange rates and risks that the Company’s hedging policy is not able to derisk and offset adverse exchange rate movements; whether the Company is able to develop, adopt, integrate, and deploy new and emerging technologies, and to leverage technological innovations, across its operations, product, and service offerings, to meet evolving customer needs and expectations; regulatory and policy incentives; the ability of the Company to maintain appropriate insurance coverage on commercially reasonable terms and at reasonable prices; risks inherent in conducting international operations, including those related to cultural, political, and economic factors in foreign jurisdictions and to corruption, sanctions, and trade compliance; Enerflex will maintain sufficient cash flow, profitability, and financial flexibility to support the ongoing payment of a sustainable quarterly cash dividend, subject to market conditions, operational performance, and board approval; Enerflex will maintain sufficient cash flow from operations, and access to credit and capital markets on reasonable commercial terms or at all, to meet its current and future obligations; the Company and its subsidiaries ability to continue to comply with covenants, financial ratios, and financial tests applicable under the Revolving Credit Facility; the viability of the Company’s information technology systems or infrastructure; information security and the adequacy of security measures in place at third-parties that provide information technology applications to the Company; the timely and cost-effective execution of projects; the Company’s reliance on contractors and sub-contractors to support project execution and delivery of products and services; and other factors, many of which are beyond the control of the Company. See Enerflex’s Annual Information Form for the year ended December 31, 2025 and in Enerflex’s management’s discussion and analysis for the year ended December 31, 2025, each accessible under the electronic profile of Enerflex on SEDAR+ and Edgar at www.sedarplus.ca and www.sec.gov/edgar, respectively.

Readers are cautioned that the foregoing list of assumptions and risk factors should not be construed as exhaustive. While the Company believes that there is a reasonable basis for the FLI included in this Form 40-F, as a result of known and unknown risks, uncertainties, and other factors, actual results, performance, or achievements could differ materially from those expressed in, or implied by, these statements. Readers are cautioned not to unduly rely on FLI.

The FLI contained herein is expressly qualified in its entirety by the above cautionary statement and is given as at the date of this Form 40-F. Other than as required by law, Enerflex disclaims any intention or obligation to update or revise any FLI, whether as a result of new information, future events, or otherwise.

CURRENCY

The Company presents its consolidated financial statements in US dollars unless otherwise specified. All dollar amounts in this Form 40-F are stated in US dollars (“$” or “US$”), except where otherwise indicated.

CANADIAN ANNUAL DISCLOSURE DOCUMENTS

The following documents are filed as exhibits to this Form 40-F and are incorporated by reference herein:

1. The Annual Information Form of the Company for the fiscal year ended December 31, 2025, which is filed as Exhibit 99.1 to this Form 40-F (the “AIF”);

2. Audited Consolidated Financial Statements of the Company for the fiscal year ended December 31, 2025, which is filed as Exhibit 99.2 to this Form 40-F (the “Annual Financial Statements”); and

3. Management’s Discussion and Analysis of the Company for the fiscal year ended December 31, 2025, which is filed as Exhibit 99.3 to this Form 40-F (the “Annual MD&A”).

CERTIFICATIONS

See Exhibits 99.4, 99.5, 99.6 and 99.7 to this Form 40-F.

DISCLOSURE CONTROLS AND PROCEDURES

Disclosure controls and procedures are designed to provide reasonable assurance that information required to be disclosed in reports filed with, or submitted to, securities regulatory authorities is recorded, processed, summarized and reported within the time periods specified under Canadian and United States securities laws. As of December 31, 2025, an evaluation was carried out under the supervision of, and with the participation of, the Company’s management, including the Chief Executive Officer and the Chief Financial Officer, of the effectiveness of the Company’s disclosure controls and procedures, as defined in the applicable Canadian and United States securities

laws. Based on that evaluation, the Chief Executive Officer and the Chief Financial Officer concluded that such disclosure controls and procedures were effective as of December 31, 2025.

MANAGEMENT’S ANNUAL REPORT ON INTERNAL CONTROL OVER FINANCIAL REPORTING

For management’s annual report on internal control over financial reporting (“ICFR”), see “Internal Control Over Financial Reporting” set forth in the Annual MD&A filed as Exhibit 99.3 to this Annual Report, incorporated herein by reference.

ATTESTATION REPORT OF THE INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

The Company’s independent registered public accounting firm, Ernst & Young LLP (PCAOB ID: 1263), which audited the consolidated financial statements included in this Annual Report on Form 40-F, has issued an attestation report on management’s assessment of the Company’s ICFR, entitled “Report of Independent Registered Public Accounting Firm”, that accompanies the Annual Financial Statements for the fiscal year ended December 31, 2025, filed as Exhibit 99.2 to this Annual Report on Form 40-F.

CHANGES IN INTERNAL CONTROL OVER FINANCIAL REPORTING

Management regularly reviews its system of ICFR and makes changes to the Company’s processes and systems to improve controls and increase efficiency, while ensuring that the Company maintains an effective internal control environment. Changes may include such activities as implementing new, more efficient systems, consolidating activities, and migrating processes.

The disclosure provided under the heading “Internal Control Over Financial Reporting” in the Annual MD&A is incorporated by reference herein. Other than as disclosed herein and under the heading “Internal Control Over Financial Reporting” in the Annual MD&A, there have been no significant changes in the design of the Company’s ICFR during the twelve months ended December 31, 2025, that would materially affect, or is reasonably likely to materially affect, the Company’s ICFR.

NOTICES PURSUANT TO REGULATION BTR

The Company did not send any notices required by Rule 104 of Regulation BTR during the year ended December 31, 2025, concerning any equity security subject to a blackout period under Rule 101 of Regulation BTR.

IDENTIFICATION OF THE AUDIT COMMITTEE

The Company has a separately designated standing Audit Committee established in accordance with section 3(a)(58)(A) of the Exchange Act. The Audit Committee is composed of Mona Hale (Chair), Ben Cherniavsky, and James Gouin, as described under “Audit Committee - Composition of the Audit Committee” in the AIF.

AUDIT COMMITTEE FINANCIAL EXPERT

The Company Board of Directors (the "Board") has determined that the Company has at least one “audit committee financial expert” (as defined in paragraph (8) of General Instruction B to Form 40-F) and that Ms. Hale, Mr. Cherniavsky, and Mr. Gouin are the Company’s “audit committee financial experts” serving on the Audit Committee of the Board. The audit committee financial experts are “independent” under applicable listing standards.

CODE OF ETHICS

The Company has a “code of ethics” (as defined in paragraph (9)(b) of General Instruction B to Form 40-F) that applies to all the Company’s employees, officers and directors, including the Chief Executive Officer, Chief Financial Officer, principal accounting officer or controller, and persons performing similar functions.

The Company’s Business Code of Conduct, as amended, is filed as Exhibit 99.9 to this annual report on Form 40-F, and is available without charge on the Company’s website at www.enerflex.com or upon request from the Corporate Secretary, Enerflex Ltd., Suite 904, 1331 Macleod Trail S.E., Calgary, Alberta, Canada, T2G 0K3 (telephone (403) 261-4280).

During the fiscal year ended December 31, 2025, there have not been any waivers of, including implicit waivers of, any provision of the Business Code of Conduct which is applicable to the Company’s Chief Executive Officer, Chief Financial Officer, principal accounting officer or controller, or persons performing similar functions and that relates to any element of the code of ethics definition enumerated in paragraph (9)(b) of General Instruction B to Form 40-F.

PRINCIPAL ACCOUNTANT FEES AND SERVICES

Ernst & Young LLP (PCAOB ID: 1263) served as the Company’s independent registered public accounting firm for the fiscal years ended December 31, 2025 and 2024.

For the years ended December 31, 2025 and 2024, Ernst & Young LLP and its affiliates billed or expect to bill, including out-of-pocket costs, $4,145,133 and $6,620,695, respectively, as detailed below:

Notes:

AUDIT COMMITTEE PRE-APPROVAL POLICIES AND PROCEDURES

For a description of the pre-approval policies and procedures of the Company’s Audit Committee, see “Audit Committee—Pre-approval Policies and Procedures” in the AIF.

No audit-related fees, tax fees or other non-audit fees were approved by the Audit Committee pursuant to paragraph (c)(7)(i)(C) of Rule 2-01 of Regulation S-X.

OFF-BALANCE SHEET ARRANGEMENTS

The Company has not entered into any “off-balance sheet arrangements”, as defined in General Instruction B(11) to Form 40-F, that have or are reasonably likely to have a current or future effect on the Company’s financial condition, changes in financial condition, revenues, expenses, results of operations, liquidity, capital expenditures or capital resources that are material to investors.

TABULAR DISCLOSURE OF CONTRACTUAL OBLIGATIONS

For tabular disclosure of the Company’s contractual obligations, see the Annual MD&A, under the heading “Contractual Obligations, Committed Capital Investment, and Off-Balance Sheet Arrangements”.

COMPARISON OF NYSE CORPORATE GOVERNANCE RULES

The Company is subject to a variety of corporate governance guidelines and requirements enacted by the Toronto Stock Exchange (the “TSX”), the Canadian securities regulatory authorities, the New York Stock Exchange (the “NYSE”) and the U.S. Securities Exchange Commission (“SEC”). The Company’s common shares are listed on the TSX and the NYSE. Sections 103.00 and 303A.11 of the NYSE Listed Company Manual permit “foreign private issuers” (as defined in Rule 3b-4 under the Exchange Act) like the Company to follow home country practices in lieu of certain provisions of the NYSE Listed Company Manual. A description of the significant ways in which the Company’s corporate governance practices differ from those followed by domestic companies pursuant to NYSE standards is as follows:

Shareholder Meeting Quorum Requirement: The NYSE is of the opinion that the quorum required for any meeting of shareholders should be sufficiently high to ensure a representative vote. The Company’s quorum requirement is set forth in its By-laws. A quorum for a meeting of the Company’s shareholders is (a) two persons present in person, each holding or representing by proxy at least one issued share of Enerflex, for the choice of a chair of the meeting and for the adjournment of the meeting to a fixed time and place and (b) for all other purposes, two persons present and holding or representing by proxy not less than 10% of the total number of Enerflex common shares entitled to be voted at the meeting.

Shareholder Approval Requirement: The NYSE rules for U.S. domestic issuers require shareholder approval of certain transactions or series of related transactions that result in the issuance of common shares, or securities convertible into or exercisable for common shares, that have, or will have upon issuance, voting power equal to or in excess of 20% of the voting power outstanding prior to the transaction or if the issuance of common shares, or securities convertible into or exercisable for common shares, are, or will be upon issuance, equal to or in excess of 20% of the number of common shares outstanding prior to the transaction.

The Company intends to follow TSX rules for shareholder approval of new issuances of its common shares. In accordance with TSX rules, shareholder approval is required for certain issuances of shares that: (i) materially affect control of the Company; or (ii) provide consideration to insiders in an aggregate of 10% or greater of the market capitalization of the Company and have not been negotiated at arm’s length. Shareholder approval is also required under TSX rules in the case of private placements: (a) for an aggregate number of listed securities issuable greater than 25% of the number of securities of the listed issuer which are outstanding, on a non-diluted basis, prior to the date of closing of the transaction if the price per security is less than the market price; or (b) that during any six-month period are to insiders for listed securities or options, rights or other entitlements to listed securities greater than 10% of the number of securities of the listed issuer which are outstanding, on a non-diluted basis, prior to the date of the closing of the first private placement to an insider during the six-month period.

Equity Compensation Plans: The NYSE rules for U.S. domestic issuers require shareholder approval of all equity compensation plans (as defined in the NYSE rules) regardless of whether new issuances, treasury shares or shares that the Company has purchased in the open market are used. Unlike the NYSE rules, there is no requirement in Canada for shareholder approval of compensation arrangements settled solely in cash or with shares purchased in the open market at fair value or for amendments to such arrangements. Enerflex intends to comply with the TSX rules that require a listed company to obtain shareholder approval of any share compensation arrangement that involves the issuance of shares from treasury or to make amendments to such arrangements that require shareholder approval (in accordance with the TSX rules and the terms of such arrangement).

The foregoing is consistent with Canadian laws, customs and practices.

RECOVERY OF ERRONEOUSLY AWARDED COMPENSATION

The Company’s Incentive Compensation Recovery Policy is filed as Exhibit 97 to this annual report on Form 40-F.

UNDERTAKING

The Company undertakes to make available, in person or by telephone, representatives to respond to inquiries made by the SEC staff, and to furnish promptly, when requested to do so by the SEC staff, information relating to: the securities in relation to which the obligation to file an annual report on Form 40-F arises; or transactions in said securities.

DISCLOSURE PURSUANT TO SECTION 13(r) OF THE EXCHANGE ACT

In accordance with Section 13(r) of the Exchange Act, the Company is required to include certain disclosures in its periodic reports if it or any of its affiliates knowingly engaged in certain specified activities during the period covered by the report. Neither the Company nor its affiliates have knowingly engaged in any transaction or dealing reportable under Section 13(r) of the Exchange Act during the year ended December 31, 2025.

EXHIBIT INDEX

SIGNATURES

Pursuant to the requirements of the Exchange Act, the Company certifies that it meets all of the requirements for filing on Form 40-F and has duly caused this annual report to be signed on its behalf by the undersigned, thereto duly authorized.