The selling stockholders named in this prospectus may use this prospectus to offer and resell from time to time up to an aggregate of 3,250,245 shares of our common stock, par value $0.50 per share, which are comprised of (i) 2,221,141 shares of common stock issued and outstanding (the “common shares”) and (ii) 1,029,104 shares of common stock issuable upon exercise of common warrants (the “Warrants”) issued by us in a private placement to the selling stockholders that are party to the Securities Purchase Agreement, dated November 24, 2025 (the “Purchase Agreement”). The common shares and the shares of common stock issuable upon exercise of the Warrants are collectively referred to herein as the “Shares”.

We are not selling any shares of our common stock under this prospectus and will not receive any of the proceeds from the sale of the Shares by the selling stockholders. We will, however, receive the net proceeds of any Warrants exercised for cash.

The selling stockholders may sell or otherwise dispose of the Shares covered by this prospectus in a number of different ways and at varying prices. We provide more information about how the selling stockholders may sell or otherwise dispose of the Shares covered by this prospectus in the section entitled “Plan of Distribution” on page 11 of this prospectus. For information on the selling stockholders, see the section entitled “Selling Stockholders” on page 8 of this prospectus. Discounts, concessions, commissions and similar selling expenses attributable to the sale of the Shares covered by this prospectus will be borne by the selling stockholders. We will pay all expenses (other than discounts, concessions, commissions and similar selling expenses) relating to the registration of the Shares with the Securities and Exchange Commission (the “SEC” or the “Commission”).

Our common stock is listed on NYSE American under the symbol “BRN.” On January 9, 2026, the last reported sale price of our common stock was $1.10 per share.

We may amend or supplement this prospectus from time to time by filing amendments or supplements as required. You should read the entire prospectus and any amendments or supplements carefully before you make your investment decision.

Investing in our securities involves risks. You should carefully read the “Risk Factors” beginning on page 4 of this prospectus before investing.

Neither the SEC nor any state securities commission has approved or disapproved of these securities or passed upon the accuracy or adequacy of this prospectus. Any representation to the contrary is a criminal offense.

This prospectus is a part of a registration statement on Form S-3 that we filed with the SEC. Under this registration statement, the selling stockholders may sell the securities described in this prospectus in one or more offerings. A prospectus supplement may add to, update or change the information contained in this prospectus. You should read this prospectus and any applicable prospectus supplement, together with the information incorporated herein by reference as described under the heading “Information Incorporated by Reference.”

You should rely only on the information that we have provided or incorporated by reference in this prospectus and any applicable prospectus supplement. We have not authorized, nor has any selling stockholder authorized, any dealer, salesman or other person to give any information or to make any representation other than those contained or incorporated by reference in this prospectus or any applicable prospectus supplement. You should not rely upon any information or representation not contained or incorporated by reference in this prospectus or any applicable prospectus supplement. We take no responsibility for and can provide no assurance as to the reliability of, any other information that others may give you.

This prospectus and any accompanying prospectus supplement do not constitute an offer to sell or the solicitation of an offer to buy any securities other than the registered securities to which they relate, nor do this prospectus and any accompanying prospectus supplement constitute an offer to sell or the solicitation of an offer to buy securities in any jurisdiction to any person to whom it is unlawful to make such offer or solicitation in such jurisdiction. You should not assume that the information contained in this prospectus or any applicable prospectus supplement is accurate on any date subsequent to the date set forth on the front of the document or that any information we have incorporated by reference is correct on any date subsequent to the date of the document incorporated by reference, even though this prospectus or any applicable prospectus supplement is delivered or securities are sold on a later date.

As used in this prospectus and unless otherwise indicated, the terms “we,” “us,” “our,” “Barnwell,” or the “Company” refer to Barnwell Industries, Inc. and its consolidated subsidiaries.

This prospectus and the documents incorporated herein by reference, contain “forward-looking statements” within the meaning of the Private Securities Litigation Reform Act of 1995 (“PSLRA”). A forward-looking statement is one which is based on current expectations of future events or conditions and does not relate to historical or current facts. These statements include various estimates, forecasts, projections of Barnwell’s future performance, statements of Barnwell’s plans and objectives and other similar statements. All such statements we make are forward-looking statements made under the safe harbor of the PSLRA, except to the extent such statements relate to the operations of a partnership or limited liability company. Forward-looking statements include phrases such as “expects,” “anticipates,” “intends,” “plans,” “believes,” “predicts,” “estimates,” “assumes,” “projects,” “may,” “will,” “will be,” “should,” or similar expressions. Although Barnwell believes that its current expectations are based on reasonable assumptions, it cannot assure that the expectations contained in such forward-looking statements will be achieved. Forward-looking statements involve risks, uncertainties and assumptions which could cause actual results to differ materially from those contained in such statements. Investors should not place undue reliance on these forward-looking statements, as they speak only as of the date of the filing of this prospectus, and Barnwell expressly disclaims any obligation or undertaking to publicly release any updates or revisions to any forward-looking statements contained herein.

Among the important factors that could cause actual results to differ materially from those in the forward-looking statements are domestic and international general economic conditions, such as recessionary trends and inflation; domestic and international political, legislative, economic, regulatory and legal actions, including changes in the policies of the Organization of the Petroleum Exporting Countries or other developments involving or affecting oil and natural gas producing countries; military conflict, embargoes, internal instability or actions or reactions of the governments of the U.S. and/or Canada in anticipation of or in response to such developments; interest costs, restrictions on production, restrictions on imports and exports in both the U.S. and Canada, the maintenance of specified reserves, tax increases and retroactive tax claims, royalty increases, expropriation of property, cancellation of contract rights, environmental protection controls, environmental compliance requirements and laws pertaining to workers’ health and safety; the condition of Hawaii’s real estate market, including the level of real estate activity and prices, the demand for new housing and second homes on the island of Hawaii, the rate of increase in the cost of building materials and labor, the introduction of building code modifications, changes to zoning laws, the condition of Hawaii’s tourism industry and the level of confidence in Hawaii’s economy; levels of land development activity in Hawaii; the potential liability resulting from pending or future litigation; the Company’s acquisition or disposition of assets; the effects of changed accounting rules under GAAP promulgated by rule-setting bodies; and the factors set forth under the heading “Risk Factors” of the Company’s annual report on Form 10-K for its fiscal year ended September 30, 2025, and in other documents filed by the Company with the SEC.

An investment in our securities involves a high degree of risk. Before deciding whether to invest in our securities, you should consider carefully the risks and uncertainties discussed below, as well as those under the heading “Risk Factors” contained in our Annual Report on Form 10-K for the year ended September 30, 2025 as filed with the SEC on December 23, 2025, and as incorporated by reference in this prospectus, as the same may be amended, supplemented or superseded by the risks and uncertainties described under similar headings in the other documents that are filed by us after the date hereof and incorporated by reference into this prospectus. Please also read carefully the section above titled “Cautionary Note Regarding Forward-Looking Statements.”

This prospectus covers the resale of 3,250,245 shares of our common stock and common stock underlying the Warrants held by the selling stockholders. Sales of substantial amounts of our common stock in the public market, or the perception that such sales might occur, could adversely affect the market price of our common stock. We cannot predict if and when selling stockholders may sell such shares in the public market.

The exercise of the Warrants will increase substantially the number of shares of common stock issued and outstanding, which will dilute the ownership interests of existing stockholders. The amount of dilution, or the reduction in value to existing shares of common stock, is determined by the amount of shares ultimately obtained upon the exercise of the Warrants relative to the number of shares of common stock outstanding at the time of exercise.

The net proceeds from any disposition of the Shares will be received by the selling stockholders. We will not receive any of the proceeds from any such Shares offered by this prospectus. We will, however, receive the net proceeds of any Warrants exercised for cash. We expect to use the proceeds received from the exercise of the Warrants, if any, for general corporate purposes, including working capital.

Our certificate of incorporation, as amended (“Certificate of Incorporation”) authorize us to issue up to 40,000,000 shares of common stock, $0.50 par value. We have one class of common stock. As of January 5, 2026, there were 12,538,064 shares of our common stock issued and outstanding. The outstanding shares of our common stock are validly issued, fully paid and nonassessable.

Voting. Holders of our Common Stock are entitled to one vote for each share held on all matters submitted to a vote of stockholders and do not have cumulative voting rights. Accordingly, holders of a majority of the shares of Common Stock entitled to vote in any election of directors may elect all of the directors standing for election. Holders of record of a majority of our Common Stock then issued and outstanding and entitled to vote, represented in person or by proxy, are necessary and sufficient to constitute a quorum for the transaction of business, except as otherwise provided by law. Except as otherwise provided by law, in all other matters the affirmative vote of a majority of the shares present in person or represented by proxy at the meeting and entitled to vote on the subject matter shall be the act of the stockholders.

Dividends. As we do not have any authorized or outstanding preferred stock, holders of Common Stock are entitled to receive proportionately any dividends that may be declared by our Board.

Liquidation and Distribution. Upon our liquidation, dissolution or winding up, the holders of Common Stock are entitled to receive proportionately our net assets available after the payment of all debts and other liabilities and subject to the prior rights of any outstanding preferred stock (if any). Holders of Common Stock have no preemptive, subscription, redemption or conversion rights. Our outstanding shares of Common Stock are, and the shares offered by us in this offering will be, when issued and paid for, fully paid and nonassessable.

Delaware law, our certificate of incorporation and our bylaws contain provisions that could have the effect of delaying, deferring or discouraging another party from acquiring control of us. These provisions, which are summarized below, are intended to discourage coercive takeover practices and inadequate takeover bids. These provisions are also designed to encourage persons seeking to acquire control of us to first negotiate with our Board.

Our bylaws establish an advance notice procedure for stockholder proposals to be brought before an annual meeting of stockholders, including proposed nominations of persons for election to the Board of Directors. Stockholders at an annual meeting may only consider proposals or nominations specified in the notice of meeting or brought before the meeting by or at the direction of the Board of Directors or by a stockholder of record on the record date for the meeting, that is entitled to vote at the meeting and that has delivered to our secretary a timely written notice in proper form of the stockholder’s intention to bring such business before the meeting. These provisions could have the effect of delaying until the next stockholder meeting stockholder actions that are favored by the holders of a majority of our outstanding voting Common Stock.

We are subject to Section 203 of the General Corporation Law of the State of Delaware, amended from time to time (the “Delaware Law”). Subject to certain exceptions, Section 203 prevents a publicly held Delaware corporation from engaging in a “business combination” with any “interested stockholder” for three years following the date that the person became an interested stockholder, unless the interested stockholder attained such status with the approval of our Board of Directors or unless the business combination is approved in a prescribed manner. A “business combination” includes, among other things, a merger or consolidation involving us and the “interested stockholder” and the sale of more than 10% of our assets. In general, an “interested stockholder” is any entity or person beneficially owning 15% or more of our outstanding voting stock and any entity or person affiliated with or controlling or controlled by such entity or person.

Our certificate of incorporation limits the personal liability of directors for breach of fiduciary duty to the maximum extent permitted by the Delaware Law. Our certificate of incorporation provides that no director will have personal liability to us or to our stockholders for monetary damages for breach of fiduciary duty or other duty as a director, except for:

Any amendment to or repeal of these provisions will not eliminate or reduce the effect of these provisions in respect of any act or failure to act, or any cause of action, suit or claim that would accrue or arise prior to any amendment or repeal or adoption of an inconsistent provision. If the Delaware Law is amended to provide for further limitations on the personal liability of directors of corporations, then the personal liability of our directors will be further limited to the greatest extent permitted by the Delaware Law.

In addition, our certificate of incorporation provides that we must indemnify our directors in accordance with Section 145 of the Delaware Law.

Our authorized but unissued shares of Common Stock and preferred stock are available for future issuance without stockholder approval, subject to any limitations imposed by the listing standards of the NYSE American. These additional shares may be used for a variety of corporate finance transactions, acquisitions and employee benefit plans. The existence of authorized but unissued and unreserved Common Stock and preferred stock could make it more difficult or discourage an attempt to obtain control of us by means of a proxy contest, tender offer, merger or otherwise.

The transfer agent and registrar for our Common Stock is Broadridge Corporate Issuer Solutions, Inc., 51 Mercedes Way, Edgewood, NY 11717.

Our Common Stock is listed on the NYSE American under the symbol “BRN”.

The shares of common stock being offered by the selling stockholders, or the Shares, are those common shares issued to the selling stockholders and the shares of common stock issuable to the selling stockholders upon exercise of the Warrants (as defined below) issued in a private placement which closed on November 28, 2025. Other than the relationships as purchasers under the Purchase Agreement (as defined below) and as otherwise described herein, to our knowledge, no material relationships exist between any of the selling stockholders and us nor have any such material relationships existed within the past three years.

On November 24, 2025, we entered into a securities purchase agreement (the “Purchase Agreement”) with certain investors (the “Purchasers”), including certain directors of the board of directors of the Company pursuant to which we issued and sold an aggregate of: (i) 2,221,141 shares of its common stock, par value $0.50 per share (the “Common Stock”), and (ii) warrants (the “Warrants”) to purchase up to 1,029,104 shares of Common Stock (the “Warrant Shares”) in a private placement (the “Private Placement”) offering of the Company’s securities (the “Offering”). The directors of the Company participating as Purchasers in the Offering and certain other Purchasers did not receive any Warrants.

The price of the shares of Common Stock sold in the Private Placement was $1.10 per share of Common Stock. The Warrants have an exercise price of $1.65 per share, can be exercised starting one hundred eighty (180) days following the date of closing of the Offering (the “Initial Exercise Date”) and will be exercisable for three years following the Initial Exercise Date.

The Offering closed on November 28, 2025 (the “Closing Date”) and the gross proceeds received from the Offering was approximately $2,443,000.

Pursuant to the terms of the Purchase Agreement, we agreed to register for resale the shares of Common Stock and the Warrant Shares and file the initial registration statement covering such resale no later than forty-five (45) days after the Closing Date.

When we refer to the “Selling Stockholders” in this prospectus, we mean the persons listed in the table below, and the pledgees, donees, transferees, assignees, successors, designees and others who later come to hold any of the Selling Stockholders’ interest in the common stock other than through a public sale. The following table sets forth, as of the date of this prospectus, the names of the Selling Stockholders, and other information regarding the beneficial ownership (as determined under Section 13(d) of the Exchange Act of 1934, as amended, and the rules and regulations thereunder) of the shares of common stock held by each of the Selling Stockholders, as of the date of this prospectus, assuming exercise of all of the Warrants held by each such Selling Stockholder on that date, without regard to any limitations on exercise. The third column lists the aggregate number of shares of common stock that the Selling Stockholders may offer pursuant to this prospectus.

The Selling Stockholders may sell all, some or none of their shares in this offering. See “Plan of Distribution” on page 11 of this prospectus.

All information with respect to the common stock ownership of the Selling Stockholders has been furnished by or on behalf of the Selling Stockholders. We believe, based on information supplied by the Selling Stockholders, that except as may otherwise be indicated in the footnotes to the table below, the Selling Stockholder has sole voting and dispositive power with respect to the shares of common stock reported as beneficially owned by the Selling Stockholders. Because the Selling Stockholders identified in the table may sell some or all of the shares of common stock beneficially owned by them and covered by this prospectus, and because there are currently no agreements, arrangements or understandings with respect to the sale of any of the shares of common stock, no estimate can be given as to the number of shares of common stock available for resale hereby that will be held by the Selling Stockholders upon termination of this offering. In addition, the Selling Stockholders may have sold, transferred or otherwise disposed of, or may sell, transfer or otherwise dispose of, at any time and from time to time, the shares of common stock they beneficially own after the date on which they provided the information set forth in the table below. We have, therefore, assumed for the purposes of the following table, that the Selling Stockholders will sell all of the shares of common stock owned beneficially that are covered by this prospectus, but will not sell any other shares of common stock presently owned. Except as set forth below, the Selling Stockholders have not held any position or office, or have otherwise had

a material relationship, with us or any of our subsidiaries within the past three years other than as a result of the ownership of our shares of common stock or other securities.

Each selling stockholder of the Shares and any of their pledgees, assignees and successors-in-interest may, from time to time, sell any or all of their respective securities covered hereby on markets or exchanges on which the Shares are listed or quoted for trading on the date in question, or in private transactions. These sales may be at fixed or negotiated prices. A selling stockholder may use any one or more of the following methods when selling securities:

A selling stockholder may also sell securities under Rule 144 or any other exemption from registration under the Securities Act, if available, rather than under this prospectus.

Broker-dealers engaged by a selling stockholder may arrange for other brokers-dealers to participate in sales. Broker-dealers may receive commissions or discounts from a selling stockholder (or, if any broker-dealer acts as agent for the purchaser of securities, from the purchaser) in amounts to be negotiated, but, except as set forth in a supplement to this prospectus, in the case of an agency transaction not in excess of a customary brokerage commission in compliance with FINRA Rule 2121; and in the case of a principal transaction a markup or markdown in compliance with FINRA Rule 2121.

A selling stockholder may enter into option or other transactions with broker-dealers or other financial institutions or create one or more derivative securities which require the delivery to such broker-dealer or other financial institution of securities offered by this prospectus, which securities such broker-dealer or other financial institution may resell pursuant to this prospectus (as supplemented or amended to reflect such transaction).

A selling stockholder and any broker-dealers or agents that are involved in selling the Shares may be deemed to be “underwriters” within the meaning of the Securities Act in connection with such sales. In such event, any commissions received by such broker-dealers or agents and any profit on the resale of the Shares purchased by them may be deemed to be underwriting commissions or discounts under the Securities Act. Each selling stockholder has informed us that it does not have any written or oral agreement or understanding, directly or indirectly, with any person to distribute the Shares.

We are required to pay certain fees and expenses incurred by us incident to the registration of the Shares. We have agreed to indemnify any selling stockholder against certain losses, claims, damages and liabilities, including liabilities under the Securities Act.

We agreed to keep this prospectus effective until the earlier of (i) the date on which the Shares may be resold by the selling stockholders without registration and without regard to any volume or manner-of-sale limitations by reason of Rule 144, without the requirement for us to be in compliance with the current public information under Rule 144 under the Securities Act or any other rule of similar effect or (ii) all of the Shares have been sold pursuant to this prospectus or Rule 144 under the Securities Act or any other rule of similar effect. The resale securities will be sold only through registered or licensed brokers or dealers if required under applicable state securities laws.

Under applicable rules and regulations under the Exchange Act, any person engaged in the distribution of the resale securities may not simultaneously engage in market making activities with respect to the common stock for the applicable restricted period, as defined in Regulation M, prior to the commencement of the distribution. In addition, the selling stockholders will be subject to applicable provisions of the Exchange Act and the rules and regulations thereunder, including Regulation M, which may limit the timing of purchases and sales of the common stock by a selling stockholder or any other person. We will make copies of this prospectus available to a selling stockholder and have informed them of the need to deliver a copy of this prospectus to each purchaser at or prior to the time of the sale (including by compliance with and reliance on Rule 172 under the Securities Act).

The validity of the shares of common stock offered hereby will be passed upon for us by Sichenzia Ross Ference Carmel LLP, New York, New York.

The consolidated balance sheets of the Company as of September 30, 2025 and 2024, the related consolidated statements of operations, comprehensive loss, equity, and cash flows for each of the two years in the period ended September 30, 2025 and the related notes, have been audited by Weaver and Tidwell, L.L.P., independent registered public accounting firm, as stated in their report which is incorporated herein by reference. Such consolidated financial statements have been incorporated herein by reference in reliance on the report of such firm given upon their authority as experts in accounting and auditing.

This prospectus constitutes a part of a registration statement on Form S-3 filed under the Securities Act. As permitted by the SEC’s rules, this prospectus and any prospectus supplement, which form a part of the registration statement, do not contain all the information that is included in the registration statement. You will find additional information about us in the registration statement. Any statements made in this prospectus or any prospectus supplement concerning legal documents are not necessarily complete and you should read the documents that are filed as exhibits to the registration statement or otherwise filed with the SEC for a more complete understanding of the document or matter.

The SEC maintains an Internet site that contains reports, proxy and information statements, and other information regarding issuers that file electronically with the SEC. The SEC’s Internet site can be found at http://www.sec.gov. You can also obtain copies of materials we file with the SEC from our website found at www.brninc.com. Information on our website does not constitute a part of, nor is it incorporated in any way, into this prospectus and should not be relied upon in connection with making an investment decision.

The SEC allows us to “incorporate by reference” into this prospectus the information in documents we file with it, which means that we can disclose important information to you by referring you to those documents. The information incorporated by reference is considered to be a part of this prospectus, and information that we file later with the SEC will automatically update and supersede this information. Any statement contained in any document incorporated or deemed to be incorporated by reference herein shall be deemed to be modified or superseded for purposes of this prospectus to the extent that a statement contained in or omitted from this prospectus or any accompanying prospectus supplement, or in any other subsequently filed document which also is or is deemed to be incorporated by reference herein, modifies or supersedes such statement. Any such statement so modified or superseded shall not be deemed, except as so modified or superseded, to constitute a part of this prospectus.

We incorporate by reference the documents listed below and any future documents that we file with the SEC (excluding any portion of such documents that are furnished and not filed with the SEC) under Sections 13(a), 13(c), 14 or 15(d) of the Exchange Act (i) after the date of the initial filing of the registration statement of which this prospectus forms a part prior to the effectiveness of the registration statement and (ii) after the date of this prospectus until the offering of the securities is terminated: