Through this prospectus we may periodically offer:

We may also offer securities of the types listed above that are convertible or exchangeable into one or more of the securities listed above.

This prospectus describes some of the general terms that may apply to these securities. The specific types, amounts, prices, and detailed terms of any of these offered securities will be determined at the time of their offering and will be described in an amendment to the registration statement of which this prospectus forms a part, or in a supplement to this prospectus, or may be set forth in one or more documents incorporated by reference in this prospectus. The securities issued under this prospectus may be offered directly or through one or more underwriters, agents or dealers, or through other means. The names of any underwriters, agents or dealers will be included in a supplement to this prospectus. The aggregate offering price of all such securities issued under this prospectus may not exceed $300,000,000.

Our common shares are traded on the Nasdaq Capital Market under the symbol “USEA”.

The aggregate market value of our outstanding common shares held by non-affiliates as of July 10, 2026 is approximately $19,165,604, based on 7,178,129 common shares held by non-affiliates as of such date, and a closing price of our common shares on the Nasdaq Capital Market of $2.67 on July 10, 2026. As of the date hereof, we have sold no securities pursuant to General Instruction I.B.5 of Form F-3 during the period of twelve calendar months immediately prior to and including the date hereof.

Investing in our securities involves a high degree of risk. See “Risk Factors” below, beginning on page 2, and in our Annual Report on Form 20-F for the year ended December 31, 2025, which is incorporated by reference herein, to read about the risks you should consider before investing in our securities.

Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.

This prospectus is part of a registration statement that we filed with the U.S. Securities and Exchange Commission, or the SEC, using a shelf registration process. Under the shelf registration process, we may sell shares of common stock (including related preferred stock purchase rights), shares of preferred stock, debt securities, warrants, purchase contracts, rights, depositary shares and units described in this prospectus from time to time in one or more offerings. This prospectus only provides you with a general description of the securities we may offer. Each time we offer securities, we will provide you with a supplement to this prospectus that will describe the specific information about the securities being offered and the specific terms of that offering. The prospectus supplement may also add, update or change the information contained in this prospectus. If there is any inconsistency between the information in this prospectus and any prospectus supplement, you should rely on the prospectus supplement. Before purchasing any securities, you should read carefully both this prospectus and any prospectus supplement, together with the additional information described below.

This prospectus and any prospectus supplement are part of a registration statement we filed with the SEC and do not contain all the information in such registration statement. Forms of the indentures and other documents establishing the terms of the offered securities are filed as exhibits to the registration statement of which this prospectus forms a part. Statements in this prospectus or any prospectus supplement about these documents are summaries and each statement is qualified in all respects by reference to the document to which it refers. You should refer to the actual documents for a more complete description of the relevant matters. For further information about us or the securities offered hereby, you should refer to the registration statement of which this prospectus forms a part, which you can obtain from the SEC as described below under the section entitled “Where You Can Find More Information”.

You should rely only on the information contained or incorporated by reference in this prospectus and in any prospectus supplement. We have not authorized any other person to provide you with different information. If anyone provides you with different or inconsistent information, you should not rely on it. We will not make an offer to sell these securities in any jurisdiction where the offer or sale is not permitted. You should assume that the information appearing in this prospectus and the applicable supplement to this prospectus is accurate as of the date on its respective cover, and that any information incorporated by reference is accurate only as of the date of the document incorporated by reference, unless we indicate otherwise. Our business, financial condition, results of operations and prospects may have changed since those dates.

We obtained certain statistical data, market data and other industry data and forecasts used or incorporated by reference into this prospectus from publicly available information. While we believe that the statistical data, industry data, forecasts and market research are reliable, we have not independently verified the data, and we do not make any representation as to the accuracy of the information.

Unless the context otherwise requires, when used in this prospectus, the terms “Company,” “United,” “we,” “us” and “our” refer to United Maritime Corporation and all of its subsidiaries, and “United Maritime Corporation” refers only to United Maritime Corporation and not to its subsidiaries. We use the term deadweight ton, or dwt, in describing the size of our vessels. Dwt, expressed in metric tons, each of which is equivalent to 1,000 kilograms, refers to the maximum weight of cargo and supplies that a vessel can carry. Unless otherwise indicated, all references in this prospectus to “$” or “dollars” are to U.S. dollars, and financial information presented in this prospectus is derived from the financial statements incorporated by reference in this prospectus that were prepared in accordance with accounting principles generally accepted in the United States, or U.S. GAAP.

This prospectus and the documents incorporated by reference into this prospectus contain certain forward-looking statements made pursuant to the safe harbor provisions of the Private Securities Litigation Reform Act of 1995. Forward-looking statements include, but are not limited to, statements regarding our or our management’s expectations, hopes, beliefs, intentions or strategies regarding the future and other statements that are other than statements of historical fact. In addition, any statements that refer to projections, forecasts or other characterizations of future events or circumstances, including any underlying assumptions, are forward-looking statements. The words “anticipate,” “believe,” “continue,” “could,” “estimate,” “expect,” “intend,” “may,” “might,” “plan,” “possible,” “potential,” “predict,” “project,” “should,” “would” and similar expressions may identify forward-looking statements, but the absence of these words does not mean that a statement is not forward-looking. Without limiting the generality of the foregoing, all statements in this registration statement concerning or relating to estimated and projected earnings, margins, costs, expenses, expenditures, cash flows, growth rates, future financial results and liquidity are forward-looking statements. In addition, we, through our senior management, from time to time may make forward-looking public statements concerning our expected future operations and performance and other developments.

The forward-looking statements in this prospectus and the documents incorporated by reference into this prospectus are based upon various assumptions, many of which are based, in turn, upon further assumptions, including without limitation, management’s examination of historical operating trends, data contained in our records and other data available from third parties. Although we believe that these assumptions were reasonable when made, because these assumptions are inherently subject to significant uncertainties and contingencies which are difficult or impossible to predict and are beyond our control, we cannot assure you that we will achieve or accomplish these expectations, beliefs or projections. As a result, you are cautioned not to rely on any forward-looking statements.

Many of these statements are based on our assumptions about factors that are beyond our ability to control or predict and are subject to risks and uncertainties that are described more fully in “Item 3. Key Information—D. Risk Factors” of our Annual Report on Form 20-F for the year ended December 31, 2025, which is incorporated by reference herein. Any of these factors or a combination of these factors could materially affect our future results of operations and the ultimate accuracy of the forward-looking statements. In addition to these important factors and matters discussed elsewhere herein and in the documents incorporated by reference herein, important factors that, in our view, could cause actual results to differ materially from those discussed in the forward-looking statements include, among other things:

Should one or more of the foregoing risks or uncertainties materialize, or should any of our assumptions prove incorrect, actual results may vary in material respects from those projected in these forward-looking statements. Consequently, there can be no assurance that actual results or developments anticipated by us will be realized or, even if substantially realized, that they will have the expected consequences to, or effects on, us. Given these uncertainties, prospective investors are cautioned not to place undue reliance on such forward-looking statements.

We undertake no obligation to update or revise any forward-looking statements, whether as a result of new information, future events or otherwise, except as may be required under applicable laws. If one or more forward-looking statements are updated, no inference should be drawn that additional updates will be made with respect to those or other forward-looking statements.

We are incorporated under the laws of the Republic of the Marshall Islands and our principal executive offices are located outside the United States. Certain of our directors and officers reside outside the United States. In addition, substantially all of our assets and the assets of certain of our directors and officers are located outside the United States. As a result, it may not be possible for you to serve legal process within the United States upon us or any of these persons. It may also not be possible for you to enforce, both in and outside the United States, judgments you may obtain in United States courts against us or these persons in any action, including actions based upon the civil liability provisions of U.S. federal or state securities laws.

Furthermore, there is substantial doubt that courts in jurisdictions outside of the U.S. (i) would enforce judgments of U.S. courts obtained in actions against us or our directors or officers based upon the civil liability provisions of applicable U.S. federal and state securities laws or (ii) would enforce, in original actions, liabilities against us or our directors or officers based on those laws.

We are United Maritime Corporation, an international shipping company specializing in worldwide seaborne transportation services. We currently operate a fleet of six dry bulk vessels, comprising two Capesize, one Kamsarmax and three Panamax vessels with an aggregate cargo-carrying capacity of approximately 666,260 dwt and an age of approximately 13.7 years.

We were incorporated under the laws of the Republic of the Marshall Islands on January 20, 2022. Our registered address is located at Ajeltake Road, Ajeltake Island, Majuro, Marshall Islands MH 96960. Our registered agent in the Republic of the Marshall Islands is The Trust Company of the Marshall Islands, Inc., Trust Company Complex, Ajeltake Road, Ajeltake Island, Majuro, Marshall Islands MH 96960. Our principal executive office is located at 154 Vouliagmenis Avenue, 166 74 Glyfada, Greece. Our principal executive office telephone number is +30 213 0181507. Our corporate website address is www.unitedmaritime.gr. The information contained on our website does not constitute part of this prospectus. The SEC maintains a website that contains reports, proxy and information statements, and other information that we file electronically at www.sec.gov.

An investment in our securities involves a high degree of risk. Before making an investment in our securities, you should carefully consider all of the information included or incorporated by reference into this prospectus, including the risks described under the heading “Item 3. Key Information-D. Risk Factors” in our Annual Report on Form 20-F for the year ended December 31, 2025, which is incorporated by reference herein, and as updated by annual and other reports and documents we file with the SEC after the date of this prospectus and that are incorporated by reference herein. Please see the section of this prospectus entitled “Where You Can Find More Information.” The occurrence of one or more of those risk factors could adversely impact our business, financial condition or results of operations.

Unless we specify otherwise in any prospectus supplement, we plan to use the net proceeds from the sale of securities offered by this prospectus to fund the expansion of our fleet and for other general corporate purposes.

Our capitalization will be set forth in our most recent Annual Report on Form 20-F, in a prospectus supplement to this prospectus or in a report on Form 6-K subsequently furnished to the SEC and specifically incorporated herein by reference.

To the extent applicable, information about the amount by which the offering price per share of our securities issued pursuant to this prospectus exceeds the net tangible book value per share of our securities following such issuance will be included in a prospectus supplement.

The following is a summary of the description of our capital stock. Because the following is a summary, it does not contain all of the information that you may find useful. For the complete terms of our capital stock, please refer to our amended and restated articles of incorporation, which have been filed as Exhibit 1.1 to our Registration Statement on Form 20-F filed on June 6, 2022, and our second amended and restated bylaws which have been filed as Exhibit 1.1 to our report on Form 6-K filed on December 27, 2023. The information contained in these exhibits is incorporated by reference herein. The Business Corporations Act of the Republic of the Marshall Islands, as amended from time to time (“BCA”) may also affect the terms of our capital stock.

For purposes of the following description of capital stock, references to “us”, “we” and “our” refer only to United Maritime Corporation and not any of its subsidiaries.

Our purpose, as stated in our amended and restated articles of incorporation, is to engage in any lawful act or activity for which corporations may now or hereafter be organized under the BCA. We are not aware of any limitations on the rights to own our securities, including rights of non-resident or foreign stockholders to hold or exercise voting rights on our securities, imposed by foreign law or by our amended and restated articles of incorporation or second amended and restated bylaws.

Our authorized capital stock consists of 2,000,000,000 shares of common stock, par value $0.0001 (“common shares”), and 100,000,000 shares of preferred stock, par value $0.0001, of which 2,000,000 shares are designated Series A Preferred Stock and 40,000 shares are designated Series B Preferred Stock. As of December 31, 2025, 9,083,645 common shares were issued and outstanding and as of July 10, 2026, 9,538,139 common shares were issued and outstanding. As of December 31, 2025 and as of July 10, 2026, no shares of Series A Preferred Stock and 40,000 shares of Series B Preferred Stock were issued and outstanding. All of our shares of stock are in registered form.

Subject to preferences that may be applicable to any outstanding preferred shares, holders of common shares are entitled to receive ratably all dividends, if any, declared by our board of directors out of funds legally available for dividends. Upon our dissolution or liquidation or the sale of all or substantially all of our assets, after payment in full of all amounts required to be paid to creditors and to the holders of preferred stock having liquidation preferences, if any, the holders of our common shares will be entitled to receive pro rata our remaining assets available for distribution. Holders of common shares do not have conversion, redemption or preemptive rights to subscribe to any of our securities. The rights, preferences and privileges of holders of common shares are subject to the rights of the holders of any preferred shares which we have issued or may issue in the future. Our common shares are not subject to any sinking fund provisions and no holder of any shares will be required to make additional contributions of capital with respect to our shares in the future.

Each outstanding share of common stock entitles the holder to one vote on all matters submitted to a vote of shareholders. Subject to preferences that may be applicable to any outstanding shares of preferred stock, holders of shares of common stock are entitled to receive ratably all dividends, if any, declared by our board of directors out of funds legally available for dividends. Upon our dissolution or liquidation or the sale of all or substantially all of our assets, after payment in full of all amounts required to be paid to creditors and to the holders of preferred stock having liquidation preferences, if any, the holders of our common stock will be entitled to receive pro rata our remaining assets available for distribution. Holders of common stock do not have conversion, redemption or preemptive rights to subscribe to any of our securities. The rights, preferences and privileges of holders of common stock are subject to the rights of the holders of our preferred stock.

We have entered into a Shareholders Rights Agreement (as amended and restated, the “Rights Agreement”) with Continental Stock Transfer & Trust Company, as Rights Agent.

Under the Rights Agreement, we declared a dividend payable of one preferred stock purchase right, or Right, for each share of common stock outstanding immediately prior to the Spin-Off. Each Right entitles the registered holder to

purchase from us one one-thousandth of a share of Series A Participating Preferred Stock, par value $0.0001, at an exercise price of $40.00 per share. The Rights will separate from the common stock and become exercisable only if a person or group acquires beneficial ownership of 10% (15% in the case of a passive institutional investor) or more of our common stock (including through entry into certain derivative positions) in a transaction not approved by our board of directors. In that situation, each holder of a Right (other than the acquiring person, whose Rights will become void and will not be exercisable) will have the right to purchase, upon payment of the exercise price, a number of shares of our common stock having a then-current market value equal to twice the exercise price. In addition, if the Company is acquired in a merger or other business combination after an acquiring person acquires 10% (15% in the case of a passive institutional investor) or more of our common stock, each holder of the Right will thereafter have the right to purchase, upon payment of the exercise price, a number of shares of common stock of the acquiring person having a then-current market value equal to twice the exercise price. The acquiring person will not be entitled to exercise these Rights. Until a Right is exercised, the holder of a Right will have no rights to vote or receive dividends or any other shareholder rights.

The Rights may have anti-takeover effects. The Rights will cause substantial dilution to any person or group that attempts to acquire us without the approval of our board of directors. As a result, the overall effect of the Rights may be to render more difficult or discourage any attempt to acquire us. Because our board of directors can approve a redemption of the Rights or a permitted offer, the Rights should not interfere with a merger or other business combination approved by our board of directors.

We have summarized the material terms and conditions of the Rights Agreement and the Rights below. For a complete description of the Rights, we encourage you to read the Rights Agreement, which we have filed as an exhibit to our Annual Report on Form 20-F for the year ended December 31, 2025, and which is incorporated by reference herein.

The Rights are attached to all certificates representing our currently outstanding common stock, or, in the case of uncertificated common shares registered in book entry form, which we refer to as “book entry shares,” by notation in book entry accounts reflecting ownership, and will attach to all common stock certificates and book entry shares we issue prior to the Rights distribution date that we describe below. The Rights are not exercisable until after the Rights distribution date and will expire at the close of business on July 1, 2032, unless we redeem or exchange them earlier as we describe below. The Rights will separate from the common stock and a Rights distribution date would occur, subject to specified exceptions, on the earlier of the following two dates:

“Acquiring person” is generally defined in the Rights Agreement as any person, together with all affiliates or associates, who beneficially owns 10% or more of the Company’s common stock then outstanding, provided that none of Stamatios Tsantanis, his immediate family members, or any of their affiliates or associates will be considered an acquiring person. However, the Company, any subsidiary of the Company or any employee benefit plan of the Company or of any subsidiary of the Company, any person holding shares of common stock for or pursuant to the terms of any such plan, or a passive institutional investor, are excluded from the definition of “acquiring person.” Inadvertent owners that would otherwise become an acquiring person, including those who would have this designation as a result of repurchases of common stock by us, will not become acquiring persons as a result of those transactions.

Our board of directors may defer the Rights distribution date in some circumstances, and some inadvertent acquisitions will not result in a person becoming an acquiring person if the person promptly divests itself of a sufficient number of shares of common stock.

Until the Rights distribution date: (i) the Rights will be evidenced by the certificates for shares of Common Stock registered in the names of the holders thereof or, in the case of uncertificated shares of Common Stock registered in book-entry form by notation in book entry accounts reflecting the ownership of such shares of Common Stock (which certificates and Book Entry Shares, as applicable, shall also be deemed to be Rights Certificates) and not by separate Rights Certificates and (ii) the right to receive Rights Certificates will be transferable only in connection with the transfer of shares of Common Stock.

As soon as practicable after the Rights distribution date, we will prepare, execute and send, or cause to be sent (and the Rights Agent will, if requested and provided with all necessary information and documents, in the discretion of the Rights Agent, at the expense of the Company, send or cause to be sent) by first-class, postage-prepaid mail, to each record holder of shares of Common Stock as of the close of business on the Rights distribution date, at the address of such holder shown on the records of the Company, or the transfer agent or registrar for the Common Stock, a Rights Certificate evidencing one Right for each share of Common Stock so held.

We will not issue Rights with any shares of common stock we issue after the Rights distribution date, except as our board of directors may otherwise determine.

If an Acquiring Person obtains beneficial ownership of 10% (15% in the case of a passive institutional investor) or more of the common shares, then each Right will entitle the holder thereof to purchase, for the Exercise Price, a number of common shares (or, in certain circumstances, cash, property or other securities of the Company) having a then-current market value of twice the Exercise Price. However, the Rights are not exercisable following the occurrence of the foregoing event until such time as the Rights are no longer redeemable by the Company, as further described below under “Redemption of Rights”.

Following the occurrence of an event set forth in preceding paragraph, all Rights that are or, under certain circumstances specified in the Rights Agreement, were beneficially owned by an Acquiring Person or certain of its transferees will be null and void.

If, after an Acquiring Person obtains 10% (15% in the case of a passive institutional investor) or more of the common shares, (i) the Company merges into another entity; (ii) an acquiring entity merges into the Company; or (iii) the Company sells or transfers 50% or more of its assets, cash flow or earning power, then each Right (except for Rights that have previously been voided as set forth above) will entitle the holder thereof to purchase, for the Exercise Price, a number of common shares of the person engaging in the transaction having a then-current market value of twice the Exercise Price.

We may adjust the purchase price of the Preferred Shares, the number of Preferred Shares issuable and the number of outstanding Rights to prevent dilution that may occur from a stock dividend, a stock split, or a reclassification of the Preferred Shares or common shares. No adjustments to the Exercise Price of less than 1% will be made.

We may redeem the Rights for $0.0001 per Right under certain circumstances. If we redeem any Rights, we must redeem all of the Rights. Once the Rights are redeemed, the only right of the holders of the Rights will be to receive the redemption price of $0.0001 per Right, payable, at the option of the Company, in cash, common shares or such other form of consideration as the Company’s board of directors shall determine. The redemption price will be adjusted if we effect a stock dividend or a stock split.

After a person or group becomes an Acquiring Person, but before an Acquiring Person owns 50% or more of the outstanding common shares, our board of directors may extinguish the Rights by exchanging one common share or an equivalent security for each Right, other than Rights held by the Acquiring Person. In certain circumstances, we may elect to exchange the Rights for cash or other securities of the Company having a value approximately equal to one common share.

The terms of the Rights and the Rights Agreement may be amended in any respect without the consent of the holders of the Rights for so long as the Rights are then redeemable. Thereafter, the terms of the Rights and the Rights Agreement may be amended without the consent of the holders of Rights, with certain exceptions, in order to (i) cure any ambiguities; (ii) correct or supplement any provision contained in the Rights Agreement that may be defective or inconsistent with any other provision therein; (iii) shorten or lengthen any time period pursuant to the Rights Agreement; or (iv) make changes that do not adversely affect the interests of holders of the Rights (other than an Acquiring Person or an affiliate or associate of an Acquiring Person).

Our board of directors is authorized to provide for the issuance of preferred stock in one or more series with designations as may be stated in the resolution or resolutions providing for the issue of such preferred stock. At the time that any series of our preferred stock is authorized, our board of directors will fix the dividend rights, any conversion rights, any voting rights, redemption provisions, liquidation preferences and any other rights, preferences, privileges and restrictions of that series, as well as the number of shares constituting that series and their designation. Our board of directors could, without shareholder approval, cause us to issue preferred stock which has voting, conversion and other rights and preferences that could adversely affect the voting power and other rights of holders of our common stock and Series B Preferred Stock, or make it more difficult to effect a change in control. In addition, preferred stock could be used to dilute the share ownership of persons seeking to obtain control of us and thereby hinder a possible takeover attempt which, if our shareholders were offered a premium over the market value of their shares, might be viewed as being beneficial to our shareholders. The material terms of any series of preferred stock that we offer through a prospectus supplement will be described in that prospectus supplement.

The following description of the characteristics of the Series B Preferred Shares is a summary and does not purport to be complete and is qualified by reference to the Statement of Designation which we have filed as an exhibit to our Annual Report on Form 20-F for the year ended December 31, 2025, and which is incorporated by reference herein.

Voting. To the fullest extent permitted by law, each Series B preferred share entitles the holder hereof to 25,000 votes per share on all matters submitted to a vote of the shareholders of the Company, provided however, that no holder of Series B Preferred Shares may exercise voting rights pursuant to Series B Preferred Shares that would result in the aggregate voting power of any beneficial owner of such shares and its affiliates (whether pursuant to ownership of Series B Preferred Shares, common shares or otherwise) to exceed 49.99% of the total number of votes eligible to be cast on any matter submitted to a vote of shareholders of the Company. To the fullest extent permitted by law, the holder of Series B Preferred Shares shall have no special voting or consent rights and shall vote together as one class with the holders of the common shares on all matters put before the shareholders.

Conversion. The Series B Preferred Shares are not convertible into common shares or any other security.

Redemption. The Series B Preferred Shares are not redeemable.

Dividends. The Series B Preferred Shares have no dividend rights.

Transferability. All issued and outstanding Series B Preferred Shares must be held of record by one holder, and the Series B Preferred Shares shall not be transferred or sold without the prior approval of our board of directors.

Liquidation Preference. Upon any liquidation, dissolution or winding up of the Company, the Series B Preferred Shares will rank pari-passu with the common shareholders and shall be entitled to receive a payment equal to $0.0001 per share. The Series B preferred holder has no other rights to distributions upon any liquidation, dissolution or winding up of the Company.

Under our second amended and restated bylaws, annual shareholder meetings will be held at a time and place selected by our board of directors. The meetings may be held in or outside of the Marshall Islands. Special meetings of the shareholders, unless otherwise prescribed by law, may be called for any purpose or purposes at any time by the chairman of the board of directors, a majority of the entire board of directors, or the chief executive officer. Notice of every annual and special meeting of shareholders shall be given at least 15 but not more than 60 days before such meeting to each shareholder of record entitled to vote thereat.

Our directors are elected by the affirmative vote of a plurality of the votes cast at a meeting of the shareholders by the holders of shares entitled to vote in the election. Our amended and restated articles of incorporation and second amended and restated bylaws do not provide for cumulative voting in the election of directors.

The board of directors must consist of at least one member and not more than thirteen. Each director shall be elected to serve until the third succeeding annual meeting of shareholders and until his successor shall have been duly

elected and qualified, except in the event of his death, resignation, removal, or the earlier termination of his term of office. The board of directors has the authority to fix the amounts which shall be payable to the members of our board of directors, and to members of any committee, for attendance at any meeting or for services rendered to us.

Our second amended and restated bylaws require parties other than the board of directors to give advance written notice of nominations for the election of directors. The entire board of directors or any individual director may be removed, with cause, by the vote of a majority of the votes eligible to be cast by the holders of outstanding shares of our capital stock then entitled to vote at an election of directors. No director may be removed without cause by either the shareholders or the board of directors. Except as otherwise provided by applicable law, cause for the removal of a director shall be deemed to exist only if the director whose removal is proposed: (i) has been convicted, or has been granted immunity to testify in any proceeding in which another has been convicted, of a felony by a court of competent jurisdiction and that conviction is no longer subject to direct appeal; (ii) has been found to have been negligent or guilty of misconduct in the performance of his duties to the Company in any matter of substantial importance to the Company by (A) the affirmative vote of at least 80% of the directors then in office at any meeting of the board of directors called for that purpose or (B) a court of competent jurisdiction; or (iii) has been adjudicated by a court of competent jurisdiction to be mentally incompetent, which mental incompetence directly affects his ability to serve as a director of the Company. These provisions may discourage, delay or prevent the removal of incumbent officers and directors.

Our amended and restated articles of incorporation and second amended and restated bylaws provide that the vote of two-thirds of the votes eligible to be cast by holders of outstanding shares of our capital stock then entitled to vote thereon is required to amend our bylaws or certain provisions of our articles of incorporation at any annual or special meeting of shareholders.

Under the BCA, our shareholders generally have the right to dissent from the sale of all or substantially all of our assets not made in the usual course of our business and receive payment of the fair value of their shares. However, the right of a dissenting shareholder to receive payment of the appraised fair value of his shares is not available under the BCA for the shares of any class or series of stock, which shares at the record date fixed to determine the shareholders entitled to receive notice of and to vote at the meeting of the shareholders to act upon the agreement of merger or consolidation, were either (i) listed on a securities exchange or admitted for trading on an interdealer quotation system or (ii) held of record by more than 2,000 holders. In the event of any further amendment of our articles of incorporation, a shareholder also has the right to dissent and receive payment for his or her shares if the amendment alters certain rights in respect of those shares. The dissenting shareholder must follow the procedures set forth in the BCA to receive payment.

Under the BCA, any of our shareholders may bring an action in our name to procure a judgment in our favor, also known as a derivative action, provided that the shareholder bringing the action is a holder of common shares both at the time the derivative action is commenced and at the time of the transaction to which the action relates.

Our second amended and restated bylaws provide that, unless we consent in writing to the selection of an alternative forum, the High Court of the Republic of Marshall Islands shall be the sole and exclusive forum for (i) any shareholders’ derivative action or proceeding brought on behalf of the Company, (ii) any action asserting a claim of breach of a fiduciary duty owed by any director, officer or employee of the Company to the Company or the Company’s shareholders, (iii) any action asserting a claim arising pursuant to any provision of the Business Corporations Act of the Republic of the Marshall Islands (as amended from time to time), or (iv) any action asserting a claim governed by the internal affairs doctrine. However, the enforceability of similar forum selection provisions in other companies’ governing documents has been challenged in legal proceedings, and it is possible that in connection with any action a court could find the forum selection provision contained in our second amended and restated bylaws to be inapplicable or unenforceable in such action. In particular, Section 27 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), creates exclusive federal jurisdiction over all suits brought to enforce any duty or liability created by

the Exchange Act or the rules and regulations thereunder. In addition, Section 22 of the Securities Act, creates concurrent jurisdiction for federal and state courts over all suits brought to enforce any duty or liability created by the Securities Act or the rules and regulations thereunder. Shareholders’ derivative actions, including those arising under the Exchange Act or Securities Act, are subject to our forum selection provision. To the extent that the exclusive forum provision would apply to restrict the courts in which our shareholders may bring claims arising under the Exchange Act or the Securities Act and the rules and regulations thereunder, there is uncertainty as to whether a court would enforce such a provision. Investors cannot waive compliance with the federal securities laws and the rules and regulations promulgated thereunder. If a court were to find the forum selection provision to be inapplicable to, or unenforceable in respect of, one or more of the specified types of actions or proceedings, we may incur additional costs associated with resolving such action in other jurisdictions, which could adversely affect our business, financial condition and results of operations. Any person or entity holding, owning, or otherwise acquiring any shares of capital stock of us shall be deemed to have notice of and consented to the forum selection provisions in our second amended and restated bylaws. Although our forum selection provisions shall not relieve us of our statutory duties to comply with the federal securities laws and the rules and regulations thereunder, and our shareholders are not deemed to have waived our compliance with these laws, rules, and regulations, as applicable, our forum selection provisions may limit a shareholder’s ability to bring a claim in a judicial forum that it finds favorable for disputes with us or our directors, officers, or other employees, which may discourage such lawsuits with respect to such claims. For more information regarding the risks connected to the forum selection provisions in our second amended and restated bylaws, see “Risk Factors—We may not achieve the intended benefits of having a forum selection provision if it is found to be unenforceable” in our Annual Report on Form 20-F for the year ended December 31, 2025.

Our second amended and restated bylaws provide that we must indemnify our directors, officers, employees and agents, if they acted in good faith and in a manner they reasonably believed to be in or not opposed to the best interests of the Company, and, with respect to any criminal action or proceeding, had no reasonable cause to believe their conduct was unlawful. We are also required to advance certain expenses (including attorney’s fees and disbursements and court costs) to our directors and officers and we may carry directors’ and officers’ insurance providing indemnification for our directors and officers for some liabilities. We believe that these indemnification provisions and this insurance are useful to attract and retain qualified directors and officers.

The indemnification provisions in our second amended and restated bylaws may discourage shareholders from bringing a lawsuit against directors and officers for breach of their fiduciary duty. These provisions may also have the effect of reducing the likelihood of derivative litigation against directors and officers, even though such an action, if successful, might otherwise benefit us and our shareholders. In addition, an investment in our common shares may be adversely affected to the extent we pay the costs of settlement and damage awards against directors and officers pursuant to these indemnification provisions.

Several provisions of our amended and restated articles of incorporation and second amended and restated bylaws may have anti-takeover effects. These provisions are intended to avoid costly takeover battles, lessen our vulnerability to a hostile change of control and enhance the ability of our board of directors to maximize shareholder value in connection with any unsolicited offer to acquire us. However, these anti-takeover provisions, which are summarized below, could also discourage, delay or prevent (1) the merger or acquisition of our company by means of a tender offer, a proxy contest or otherwise, that a shareholder may consider in its best interest and (2) the removal of incumbent officers and directors.

Our amended and restated articles of incorporation provide for the division of our board of directors into three classes of directors, with each class as nearly equal in number as possible, serving staggered, three-year terms.

Approximately one-third of our board of directors will be elected each year. This classified board provision could discourage a third party from making a tender offer for our shares or attempting to obtain control of our company. It could also delay shareholders who do not agree with the policies of the board of directors from removing a majority of the board of directors for two years.

Our amended and restated articles of incorporation and second amended and restated bylaws prohibit cumulative voting in the election of directors. Our second amended and restated bylaws require parties other than our board of

directors to give advance written notice of nominations for the election of directors. Our second amended and restated bylaws also provide that our directors may be removed only for cause and only upon the affirmative vote of two-thirds of the votes eligible to be cast by holders of outstanding shares of our capital stock then entitled to vote at an election of directors. These provisions may discourage, delay or prevent the removal of incumbent officers and directors.

Our second amended and restated bylaws provide that any action required or permitted to be taken by our shareholders must be effected at an annual or special meeting of shareholders or by the unanimous written consent of our shareholders.

Our second amended and restated bylaws provide that the chairman of the board of directors, a majority of the board of directors, or the chief executive officer may call special meetings of our shareholders and the business transacted at the special meeting is limited to the purposes stated in the notice. Accordingly, a shareholder may be prevented from calling a special meeting for shareholder consideration of a proposal over the opposition of our board of directors and shareholder consideration of a proposal may be delayed until the next annual meeting.

Our second amended and restated bylaws provide that shareholders seeking to nominate candidates for election as directors or to bring business before an annual meeting of shareholders must provide timely notice of their proposal in writing. Our second amended and restated bylaws also specify requirements as to the form and content of a shareholder’s notice. These provisions may impede shareholders’ ability to bring matters before an annual meeting of shareholders or make nominations for directors at an annual meeting of shareholders.

Under the terms of our amended and restated articles of incorporation, our board of directors has authority, without any further vote or action by our shareholders, to issue up to 100,000,000 shares of blank check preferred stock. Our board of directors may issue shares of preferred stock on terms calculated to discourage, delay or prevent a change of control of our company or the removal of our management.

Although the BCA does not contain specific provisions regarding “business combinations” between companies organized under the laws of the Marshall Islands and “interested shareholders,” we will include these provisions in our amended and restated articles of incorporation. Specifically, our amended and restated articles of incorporation will prohibit us from engaging in a “business combination” with certain persons for three years following the date the person becomes an interested shareholder. Interested shareholders generally include:

As of July 10, 2026, we had Class A Warrants to purchase up to 6,962,770 common shares outstanding. The following summary of certain terms and provisions of the Class A Warrants is not complete and is subject to, and qualified in its entirety by the provisions of the form of Class A Warrant, which we have filed as an exhibit to our Annual Report on Form 20-F for the year ended December 31, 2025, and which is incorporated by reference herein. Prospective purchasers should carefully review the terms and provisions set forth in the form of Class A Warrant.

Exercisability. The Class A Warrants are exercisable at any time after their original issuance through July 20, 2027, the date that is five years after their original issuance. The Class A Warrants are exercisable, at the option of each holder, in whole or in part by delivering to us a duly executed exercise notice and, at any time a registration statement registering the issuance of the common shares underlying the Class A Warrants under the Securities Act is effective and available for the issuance of such shares, or an exemption from registration under the Securities Act is available for the issuance of such shares, by payment in full in immediately available funds for the number of common shares purchased upon such exercise. If a registration statement registering the issuance of the common shares underlying the Class A Warrants under the Securities Act is not effective or available, the holder may, in its sole discretion, elect to exercise the

Class A Warrant through a cashless exercise, in which case the holder would receive upon such exercise the net number of common shares determined according to the formula set forth in the Class A Warrant. No fractional common shares will be issued in connection with the exercise of a Class A Warrant. In lieu of fractional shares, we will pay the holder an amount in cash equal to the fractional amount multiplied by the exercise price.

Exercise Limitation. A holder will not have the right to exercise any portion of the Class A Warrants if the holder (together with its affiliates) would beneficially own in excess of 4.99% (or, upon election by a holder prior to the issuance of any warrants, 9.99%) of the number of shares of our common shares outstanding immediately after giving effect to the exercise, as such percentage ownership is determined in accordance with the terms of the warrants. However, any holder may increase or decrease such percentage to any other percentage not in excess of 9.99%, upon at least 61 days’ prior notice from the holder to us with respect to any increase in such percentage.

Exercise Price. The exercise price per whole common share purchasable upon exercise of the Class A Warrants is $2.25 per share, subject to adjustment pursuant to the terms of such warrants. The exercise price of the Class A Warrants may also be reduced to any amount and for any period of time at the sole discretion of our board of directors. The exercise price and number of common shares issuable upon exercise will adjust in the event of certain stock dividends and distributions, stock splits, stock combinations, reclassifications or similar events affecting our common shares.

Transferability. Subject to applicable laws, the Class A Warrants may be offered for sale, sold, transferred or assigned without our consent.

Exchange Listing. We do not intend to apply for the listing of the Class A Warrants on any stock exchange. Without an active trading market, the liquidity of the Class A Warrants will be limited.

Warrant Agent. The Class A Warrants are issued in registered form under a warrant agreement between Continental Stock Transfer & Trust Company, as warrant agent, and us. The Class A Warrants shall initially be represented only by one or more global warrants deposited with the warrant agent, as custodian on behalf of The Depository Trust Company (DTC) and registered in the name of Cede & Co., a nominee of DTC, or as otherwise directed by DTC.

Rights as a Shareholder. Except as otherwise provided in the Class A Warrants or by virtue of such holder’s ownership of our common shares, the holder of a Class A Warrant does not have the rights or privileges of a holder of our common shares, including any voting rights, until the holder exercises the warrant.

Fundamental Transactions. In the event of a fundamental transaction, as described in the Class A Warrants and generally including, with certain exceptions, any reorganization, recapitalization or reclassification of our common shares, the sale, transfer or other disposition of all or substantially all of our properties or assets, our consolidation or merger with or into another person, the acquisition of more than 50% of our outstanding common shares, or any person or group becoming the beneficial owner of 50% of the voting power represented by our outstanding common shares, the holders of the Class A Warrants will be entitled to receive upon exercise of the warrants the kind and amount of securities, cash or other property that the holders would have received had they exercised the warrants immediately prior to such fundamental transaction. Additionally, as more fully described in the Class A Warrant, in the event of certain fundamental transactions, the holders of the Class A Warrants will be entitled to receive consideration in an amount equal to the Black Scholes value of the Class A Warrants on the date of consummation of such transaction.

Governing Law. The Class A Warrants and Warrant Agreement are governed by New York law.

Continental Stock Transfer & Trust Company is the transfer agent and registrar for our common shares and the warrant agent for our Class A Warrants.

Our common shares (together with the related Rights) trade on the Nasdaq Capital Market under the symbol “USEA”.

Our corporate affairs are governed by our amended and restated articles of incorporation, second amended and restated bylaws and the BCA. The provisions of the BCA resemble provisions of the corporation laws of a number of states in the United States. While the BCA also provides that, with respect to non-resident corporations like us, it is to be applied and construed to make the BCA uniform with the laws of the State of Delaware and other states with substantially similar legislative provisions (and adopts their case law to the extent they do not conflict with the BCA), there have been few court cases interpreting the BCA in the Republic of the Marshall Islands and we cannot predict whether Marshall Islands courts would reach the same conclusions as courts in the United States. Accordingly, you may have more difficulty in protecting your interests under Marshall Islands law in the face of actions by our management, directors or controlling shareholders than would shareholders of a corporation incorporated in a United States jurisdiction that has developed a substantial body of case law. Furthermore, the Marshall Islands lacks a bankruptcy statute, and in the event of any bankruptcy, insolvency, liquidation, dissolution, reorganization or similar proceeding involving the Company, the bankruptcy laws of the United States or of another country having jurisdiction over the Company would apply. The following table provides a comparison between certain statutory provisions of the BCA and the Delaware General Corporation Law relating to shareholders’ rights.

The material terms of any series of preferred stock that we offer through a prospectus supplement, together with any material U.S. federal income tax considerations relating to such preferred stock, will be described in that prospectus supplement.

Our board of directors is authorized to provide for the issuance of preferred stock in one or more series with designations as may be stated in the resolution or resolutions providing for the issue of such preferred stock. At the time that any series of our preferred stock is authorized, our board of directors will fix the dividend rights, any conversion rights, any voting rights, redemption provisions, liquidation preferences and any other rights, preferences, privileges and restrictions of that series, as well as the number of shares constituting that series and their designation. Our board of directors could, without shareholder approval, cause us to issue preferred stock which has voting, conversion and other rights and preferences that could adversely affect the voting power and other rights of holders of our common stock and Series B Preferred Stock, or make it more difficult to effect a change in control. In addition, preferred stock could be used to dilute the share ownership of persons seeking to obtain control of us and thereby hinder a possible takeover attempt which, if our shareholders were offered a premium over the market value of their shares, might be viewed as being beneficial to our shareholders.

We may offer and issue debt securities from time to time in one or more series, under one or more indentures, each dated as of a date on or prior to the issuance of the debt securities to which it relates, pursuant to an applicable prospectus supplement. We may issue senior debt securities and subordinated debt securities pursuant to separate indentures, a senior indenture and a subordinated indenture, respectively, in each case between us and the trustee named in the indenture. We have filed forms of these documents as exhibits to the registration statement of which this prospectus forms a part. We refer to any applicable prospectus supplement, amendment to the registration statement and/or Exchange Act reports as “subsequent filings”. The senior indenture and the subordinated indenture, as amended or supplemented from time to time, are each referred to individually as an “indenture” and collectively as the “indentures”. Each indenture will be subject to and governed by the Trust Indenture Act of 1939, as amended, or the Trust Indenture Act, and will be construed in accordance with and governed by the laws of the State of New York (without giving effect to any principles thereof relating to conflicts of law that would result in the application of the laws of any other jurisdiction) unless otherwise stated in the applicable prospectus supplement and indenture (or post-effective amendment hereto). Each indenture will contain the specific terms of any series of debt securities or provide that those terms must be set forth in or determined pursuant to, an authorizing resolution, as defined in the applicable prospectus supplement or a supplemental indenture, if any, relating to such series.

The following description sets forth certain general terms and provisions of the debt securities. The particular terms and provisions of the debt securities offered by any prospectus supplement, and the extent to which the general terms and provisions described below may apply to the offered debt securities, will be described in the applicable subsequent filings. The statements below are not complete and are subject to, and are qualified in their entirety by reference to, all of the provisions of the applicable indenture. The specific terms of any debt securities that we may offer, including any modifications of, or additions to, the general terms described below as well as any applicable material U.S. federal income tax considerations concerning the ownership of such debt securities will be described in the applicable prospectus supplement and indenture and, as applicable, supplemental indenture. Accordingly, for a complete description of the terms of a particular issue of debt securities, the general description of the debt securities set forth below should be read in conjunction with the applicable prospectus supplement and indenture, as amended or supplemented from time to time.

We expect that neither indenture will limit the amount of debt securities which may be issued and that each indenture will provide that debt securities may be issued in one or more series.

We expect that the subsequent filings related to a series of offered debt securities will describe the following terms of the series:

Subsequent filings may include additional terms not listed above. Unless otherwise indicated in subsequent filings with the SEC relating to the indenture, principal, premium and interest will be payable and the debt securities will be transferable at the corporate trust office of the applicable trustee. Unless other arrangements are made or set forth in subsequent filings or a supplemental indenture, principal, premium and interest will be paid by checks mailed to the registered holders at their registered addresses.

Unless otherwise indicated in subsequent filings with the SEC, the debt securities will be issued only in fully registered form without coupons, in denominations of $1,000 or any integral multiple thereof. No service charge will be made for any transfer or exchange of the debt securities, but we may require payment of a sum sufficient to cover any tax or other governmental charge payable in connection with these debt securities.

Some or all of the debt securities may be issued as discounted debt securities, bearing no interest or interest at a rate which at the time of issuance is below market rates, to be sold at a substantial discount below the stated principal amount. United States federal income tax consequences and other special considerations applicable to any discounted securities will be described in subsequent filings with the SEC relating to those securities.

We refer you to the applicable subsequent filings for the particular terms and provisions of the debt securities offered by any prospectus supplement.

We may issue senior debt securities under a senior debt indenture. These senior debt securities would rank on an equal basis with all our other unsubordinated debt.

We may issue subordinated debt securities under a subordinated debt indenture. These subordinated debt securities would rank subordinate and junior in priority of payment to certain of our other indebtedness to the extent described in the applicable prospectus supplement.

Any series of offered debt securities may have covenants in addition to or differing from those included in the applicable indenture which will be described in subsequent filings prepared in connection with the offering of such securities, limiting or restricting, among other things:

We expect that each indenture and the rights of the respective holders generally may be modified by us only with the consent of holders of not less than a majority in aggregate principal amount of the outstanding debt securities of all series under the respective indenture affected by the modification, taken together as a class. But we expect that no modification that:

will be effective against any holder without his consent.

Additionally, certain changes under each indenture will not require the consent of any holders. These types of changes are generally limited to clarifications of ambiguities, omissions, defects and inconsistencies in each indenture and amendments, supplements and other changes that would not adversely affect the holders of outstanding debt securities under each indenture, such as adding security, covenants, additional events of default or successor trustees.

We expect that each indenture will define an event of default for the debt securities of any series as being any one of the following events:

An event of default of one series of debt securities will not necessarily constitute an event of default with respect to any other series of debt securities.

There may be such other or different events of default as described in an applicable subsequent filing with respect to any class or series of offered debt securities.

We expect that under each indenture, in case an event of default occurs and continues for the debt securities of any series, the applicable trustee or the holders of not less than 25% in aggregate principal amount of the debt securities then outstanding of that series may declare the principal and accrued but unpaid interest of the debt securities of that series to be due and payable. Further, any event of default for the debt securities of any series which has been cured is expected to be permitted to be waived by the holders of a majority in aggregate principal amount of the debt securities of that series then outstanding.

We expect that each indenture will require us to file annually, after debt securities are issued under that indenture, with the applicable trustee a written statement signed by two of our officers as to the absence of material defaults under the terms of that indenture. We also expect that each indenture will provide that the applicable trustee may withhold notice to the holders of any default if it considers it in the interest of the holders to do so, except notice of a default in payment of principal, premium or interest.

Subject to the duties of the trustee in case an event of default occurs and continues, we expect that each indenture will provide that the trustee is under no obligation to exercise any of its rights or powers under that indenture at the request, order or direction of holders unless the holders have offered to the trustee reasonable indemnity. Subject to these provisions for indemnification and the rights of the trustee, each indenture is expected to provide that the holders of a majority in principal amount of the debt securities of any series then outstanding have the right to direct the time, method and place of conducting any proceeding for any remedy available to the trustee or exercising any trust or power conferred on the trustee as long as the exercise of that right does not conflict with any law or the indenture.

The terms of each indenture are expected to provide us with the option to be discharged from any and all obligations in respect of the debt securities issued thereunder upon the deposit with the trustee, in trust, of money or U.S. government obligations, or both, which through the payment of interest and principal will provide money in an amount sufficient to pay any installment of principal, premium and interest on, and any mandatory sinking fund payments in respect of, the debt securities on the stated maturity of the payments in accordance with the terms of the debt securities and the indenture governing the debt securities.

We expect that this right may only be exercised if, among other things, we have received from, or there has been published by, the United States Internal Revenue Service a ruling to the effect that such a discharge will not be deemed, or result in, a taxable event with respect to holders. This discharge would not apply to our obligations to register the transfer or exchange of debt securities, to replace stolen, lost or mutilated debt securities, to maintain paying agencies and hold moneys for payment in trust.

We expect that the terms of each indenture will provide us with the right to omit complying with specified covenants and specified events of default described in a subsequent filing upon the deposit with the trustee, in trust, of money or U.S. government obligations, or both, which through the payment of interest and principal will provide money in an amount sufficient to pay any installment of principal, premium and interest on, and any mandatory sinking fund payments in respect of, the debt securities on the stated maturity of the payments in accordance with the terms of the debt securities and the indenture governing the debt securities.

We expect that to exercise this right we will also be required to deliver to the trustee an opinion of counsel to the effect that we have received from, or there has been published by, the United States Internal Revenue Service a ruling to the effect that the deposit and related covenant defeasance will not cause the holders of such series to recognize income, gain or loss for United States federal income tax purposes.

A subsequent filing may further describe the provisions, if any, of any particular series of offered debt securities permitting a discharge defeasance.

Each debt security will be represented either by a certificate issued in definitive form to a particular investor or by one or more global securities representing the entire issuance of securities. Both certificated securities in definitive form and global securities may be issued either in registered form, where our obligation runs to the holder of the security named on the face of the security, or in bearer form, where our obligation runs to the bearer of the security.

Definitive securities name you or your nominee as the owner of the security, other than definitive bearer securities, which name the bearer as owner, and in order to transfer or exchange these securities or to receive payments other than interest or other interim payments, you or your nominee must physically deliver the securities to the trustee, registrar, paying agent or other agent, as applicable.

Global securities name a depositary or its nominee as the owner of the debt securities represented by these global securities, other than global bearer securities, which name the bearer as owner. The depositary maintains a computerized system that will reflect each investor’s beneficial ownership of the securities through an account maintained by the investor with its broker/dealer, bank, trust company or other representative, as we explain more fully below.

We may issue the debt securities in the form of one or more fully registered global securities that will be deposited with a depositary or its nominee identified in the applicable prospectus supplement and registered in the name of that depositary or nominee. In those cases, one or more registered global securities will be issued in a denomination or aggregate denominations equal to the portion of the aggregate principal or face amount of the securities to be represented by registered global securities. Unless and until it is exchanged in whole for securities in definitive registered form, a registered global security may not be transferred except as a whole by and among the depositary for the registered global security, the nominees of the depositary or any successors of the depositary or those nominees. If not described below, any specific terms of the depositary arrangement with respect to any debt securities to be represented by a registered global security will be described in the prospectus supplement relating to those debt securities. We anticipate that the following provisions will apply to all depositary arrangements:

Ownership of beneficial interests in a registered global security will be limited to persons, called participants, that have accounts with the depositary or persons that may hold interests through participants. Upon the issuance of a registered global security, the depositary will credit, on its book-entry registration and transfer system, the participants’ accounts with the respective principal or face amounts of the securities beneficially owned by the participants. Any dealers, underwriters or selling agents participating in the distribution of the securities will designate the accounts to be credited. Ownership of beneficial interests in a registered global security will be shown on, and the transfer of ownership interests will be effected only through, records maintained by the depositary, with respect to interests of

participants, and on the records of participants, with respect to interests of persons holding through participants. The laws of some jurisdictions may require that some purchasers of securities take physical delivery of these securities in definitive form. These laws may impair your ability to own, transfer or pledge beneficial interests in registered global securities. So long as the depositary, or its nominee, is the registered owner of a registered global security, that depositary or its nominee, as the case may be, will be considered the sole owner or holder of the securities represented by the registered global security for all purposes under the indenture.

Except as described below, owners of beneficial interests in a registered global security will not be entitled to have the securities represented by the registered global security registered in their names, will not receive or be entitled to receive physical delivery of the securities in definitive form and will not be considered the owners or holders of the securities under the indenture. Accordingly, each person owning a beneficial interest in a registered global security must rely on the procedures of the depositary for that registered global security and, if that person is not a participant, on the procedures of the participant through which the person owns its interest in that registered global security, to exercise any rights of a holder under the indenture. We understand that under existing industry practices, if we request any action of holders of a registered global security or if an owner of a beneficial interest in a registered global security desires to give or take any action that a holder is entitled to give or take under the indenture, the depositary for the registered global security would authorize the participants holding the relevant beneficial interests to give or take that action, and the participants would authorize beneficial owners owning through them to give or take that action or would otherwise act upon the instructions of beneficial owners holding through them.

Principal, premium, if any, and interest payments on debt securities represented by a registered global security registered in the name of a depositary or its nominee will be made to the depositary or its nominee, as the case may be, as the registered owner of the registered global security. None of us, the trustee or any other agent of us or agent of the trustee will have any responsibility or liability to owners of beneficial interests for any aspect of the records relating to payments made on account of beneficial ownership interests in the registered global security or for maintaining, supervising or reviewing any records relating to those beneficial ownership interests. We expect that the depositary for any of the securities represented by a registered global security, upon receipt of any payment of principal, premium, interest or other distribution of underlying securities or other property to holders on that registered global security, will immediately credit participants’ accounts in amounts proportionate to their respective beneficial interests in that registered global security as shown on the records of the depositary. We also expect that payments by participants to owners of beneficial interests in a registered global security held through participants will be governed by standing customer instructions and customary practices, as is now the case with the securities held for the accounts of customers in bearer form or registered in “street name,” and will be the responsibility of those participants.

We expect that the indenture will provide that if the depositary for any of these securities represented by a registered global security is at any time unwilling or unable to continue as depositary or ceases to be a clearing agency registered under the Exchange Act, and a successor depositary registered as a clearing agency under the Exchange Act is not appointed by us within 90 days, we will be required to issue securities in definitive form in exchange for the registered global security that had been held by the depositary. In addition, the indenture is expected to allow us to decide, at any time and in our sole discretion, to not have any of the securities represented by one or more registered global securities. If we make that decision, we will issue securities in definitive form in exchange for all of the registered global security or securities representing those securities. Any securities issued in definitive form in exchange for a registered global security will be registered in the name or names that the depositary gives to the relevant trustee or other relevant agent of ours or theirs. It is expected that the depositary’s instructions will be based upon directions received by the depositary from participants with respect to ownership of beneficial interests in the registered global security that had been held by the depositary.

If we issue registered global securities, we expect that the Depository Trust Company, or DTC, will act as depository and the securities will be registered in the name of Cede & Co., as DTC’s nominee.

We may issue warrants to purchase any of our debt or equity securities or other rights, including rights to receive payment in cash or securities based on the value, rate or price of one or more specified currencies, securities or indices, or any combination of the foregoing. Warrants may be issued independently or together with any other securities and may be attached to, or separate from, such securities. Each series of warrants will be issued under a separate warrant agreement to be entered into between us and a warrant agent. The terms of any warrants to be issued and a description of the material provisions of the applicable warrant agreement will be set forth in the applicable prospectus supplement. We expect that such terms will include, among others:

We may issue purchase contracts for the purchase or sale of debt or equity securities issued by us, a basket of such securities, an index or indices of such securities, or any combination of the above as specified in the applicable prospectus supplement; or currencies.

Each purchase contract will entitle the holder thereof to purchase or sell, and obligate us to sell or purchase, on specified dates, such securities or currencies at a specified purchase price, which may be based on a formula, all as set forth in the applicable prospectus supplement. Any purchase contracts we issue will be physically settled by delivery of the securities or, in the case of purchase contracts on underlying currencies, by delivering the underlying currencies, as set forth in the applicable prospectus supplement. The applicable prospectus supplement will also specify the methods by which the holders may purchase or sell such securities or currencies and any acceleration, cancellation or termination provisions, provisions relating to U.S. federal income tax considerations, if any, or other provisions relating to the settlement of a purchase contract.

The purchase contracts may require the holders thereof to secure their obligations in a specified manner to be described in the applicable prospectus supplement. Alternatively, purchase contracts may require holders to satisfy their obligations thereunder when the purchase contracts are issued. Our obligation to settle such pre-paid purchase contracts on the relevant settlement date may constitute indebtedness. Accordingly, pre-paid purchase contracts will be issued under either a senior indenture or subordinated indenture.

We may issue rights to purchase our securities. These rights may be issued independently or together with any other security offered by this prospectus and may or may not be transferable by the shareholder receiving the rights in the rights offering. In connection with any rights offering, we may enter into a standby underwriting agreement with one or more underwriters pursuant to which the underwriter will purchase any securities that remain unsubscribed for upon completion of the rights offering.

The applicable prospectus supplement relating to any rights will describe the terms of the offered rights, including, where applicable, the following:

The description in the applicable prospectus supplement of any rights we offer will not necessarily be complete and will be qualified in its entirety by reference to the applicable rights certificate or rights agreement, which will be filed with the SEC if we offer rights. For more information on how you can obtain copies of any rights certificate or rights agreement if we offer rights, see “Where You Can Find More Information” of this prospectus. We urge you to read the applicable rights certificate, the applicable rights agreement and any applicable prospectus supplement in their entirety.

We may issue fractional shares of preferred stock, rather than full shares of preferred stock. If we do so, we may issue receipts for depositary shares that each represent a fraction of a share of a particular series of preferred stock. A related prospectus supplement will indicate that fraction. The shares of preferred stock represented by depositary shares will be deposited under a depositary agreement between us and a bank or trust company that is selected by us, which we refer to as the “bank depositary.” Each owner of a depository share will be entitled to all the right, preferences and privileges of the preferred stock represented by the depositary share. The depositary share will be evidenced by depositary receipts issued pursuant to the depositary agreement. Depositary receipts will be distributed to those persons purchasing the fractional shares of preferred stock in accordance with the terms of the offering.

The forms of the depositary agreement and the depository receipts relating to any particular issue of depositary shares will be filed with the SEC each time we issue depositary shares, and any prospectus supplement relating to any particular depositary shares will describe, among other things, the following:

You should read the particular terms of any depositary shares and any depositary receipts that we offer and any deposit agreement relating to a particular series of preferred shares which will be described in more detail in a prospectus supplement. A copy of the form of deposit agreement, including the form of depositary receipt, will be filed with the SEC at the time of the offering and incorporated by reference into the registration statement of which this prospectus forms a part. You can obtain copies of these documents when they are filed by following the directions outlined in “Where You Can Find More Information.”

As specified in the applicable prospectus supplement, we may issue units consisting of one or more of our depositary shares, rights, purchase contracts, warrants, debt securities, shares of preferred stock, shares of common stock (including preferred stock purchase rights) or any combination of such securities. The applicable prospectus supplement will describe, to the extent applicable:

Our most recently filed Annual Report on Form 20-F provides a discussion of the material U.S. federal income tax considerations and Marshall Islands tax considerations that may be relevant to prospective investors in our securities. The applicable prospectus supplement may also contain information about any material U.S. federal income tax considerations and any material non-U.S. tax considerations relating to the securities covered by such prospectus supplement.

We may sell or distribute the securities included in this prospectus through underwriters, through agents, to dealers, in private transactions, at market prices prevailing at the time of sale, at prices related to market prices, at a fixed price or prices subject to change, at varying prices determined at the time of sale (which may be above or below market prices prevailing at the time of sale) or at negotiated prices.

In addition, we may sell some or all of our securities included in this prospectus through:

In addition, we may enter into options or other types of transactions that require us to deliver our securities to a broker-dealer, who will then resell or transfer the securities under this prospectus. We may enter into hedging transactions with respect to our securities. For example, we may:

We may enter into derivative transactions with third parties, or sell securities not covered by this prospectus to third parties in privately negotiated transactions. If the applicable prospectus supplement indicates, in connection with those derivatives, the third parties may sell securities covered by this prospectus and the applicable prospectus supplement, including in short sale transactions. If so, the third party may use securities pledged by us or borrowed from us or others to settle those sales or to close out any related open borrowings of stock, and may use securities received from us in settlement of those derivatives to close out any related open borrowings of stock. The third party in such sale transactions will be an underwriter and, if not identified in this prospectus, will be identified in the applicable prospectus supplement (or a post-effective amendment). In addition, we may otherwise loan or pledge securities to a financial institution or other third party that in turn may sell the securities short using this prospectus. Such financial institution or other third party may transfer its economic short position to investors in our securities or in connection with a concurrent offering of other securities.

Any broker-dealers or other persons acting on our behalf that participate with us in the distribution of the securities may be deemed to be underwriters and any commissions received or profit realized by them on the resale of the securities may be deemed to be underwriting discounts and commissions under the Securities Act of 1933, as amended, or the Securities Act. As of the date of this prospectus, we are not a party to any agreement, arrangement or understanding between any broker or dealer and us with respect to the offer or sale of the securities pursuant to this prospectus.

At the time that any particular offering of securities is made, to the extent required by the Securities Act, a prospectus supplement will be distributed, setting forth the terms of the offering, including the aggregate number of securities being offered, the purchase price of the securities, the initial offering price of the securities, the names of any underwriters, dealers or agents, any discounts, commissions and other items constituting compensation from us and any discounts, commissions or concessions allowed or reallowed or paid to dealers. Furthermore, we, our executive officers, our directors and major shareholders may agree, subject to certain exemptions, that for a certain period from the date of the prospectus supplement under which the securities are offered, we and they will not, without the prior written consent of an underwriter, offer, sell, contract to sell, pledge or otherwise dispose of any of our common shares or any securities convertible into or exchangeable for common shares. However, an underwriter, in its sole discretion, may release any

of the securities subject to these lock-up agreements at any time without notice. We expect an underwriter to exclude from these lock-up agreements securities exercised and/or sold pursuant to trading plans entered into by us pursuant to Rule 10b5-1 under the Exchange Act, that are in place at the time of an offering pursuant to this prospectus and any applicable prospectus supplement hereto that provide for periodic sales of our securities on the basis of parameters described in such trading plans.

Underwriters or agents could make sales in privately negotiated transactions and/or any other method permitted by law, including sales deemed to be an at-the-market offering as defined in Rule 415 promulgated under the Securities Act, which includes sales made directly on or through the Nasdaq Capital Market, the existing trading market for our shares of common stock, or sales made to or through a market maker other than on an exchange.

We will bear costs relating to all of the securities offered and sold by us under this registration statement.

We estimate the expenses in connection with the issuance and distribution of the common shares being registered under the registration statement of which this prospectus forms a part, all of which will be paid by us.

The validity of the securities offered by this prospectus and certain other legal matters relating to United States and Marshall Islands law are being passed upon for us by Watson Farley & Williams LLP, New York, New York.

The consolidated financial statements of United Maritime Corporation appearing in United Maritime Corporation’s Annual Report (Form 20-F) for the year ended December 31, 2025, have been audited by Ernst & Young (Hellas) Certified Auditors Accountants S.A., independent registered public accounting firm, as set forth in their report thereon, included therein, and incorporated herein by reference. Such consolidated financial statements are incorporated herein by reference in reliance upon such report given on the authority of such firm as experts in accounting and auditing.

Ernst & Young (Hellas) Certified Auditors Accountants S.A. is located at 8B Chimarras Street, 151 25, Maroussi, Athens, Greece and is registered as a corporate body with the public register for company auditors-accountants kept with the Body of Certified Auditors Accountants, or SOEL, Greece with registration number 107.

We have filed with the SEC a registration statement with respect to the common shares offered hereby. This prospectus is a part of that registration statement, which includes additional information. This prospectus does not contain all of the information set forth in the registration statement. Each statement made in this prospectus concerning a document filed as an exhibit to the registration statement is qualified by reference to that exhibit for a complete statement of its provisions. The registration statement, including its exhibits and schedules, may be inspected and copied at the public reference facilities maintained by the SEC at 100 F Street, N.E., Washington, D.C. 20549. The SEC maintains a website (http://www.sec.gov) that contains reports, proxy and information statements and other information regarding registrants that file electronically with the SEC.

We will furnish holders of our common shares with annual reports containing audited financial statements and a report by our independent registered public accounting firm. The audited financial statements will be prepared in accordance with U.S. GAAP. As a “foreign private issuer,” we are exempt from the rules under the Exchange Act prescribing the furnishing and content of proxy statements to shareholders. While we furnish proxy statements to shareholders in accordance with the rules of Nasdaq, those proxy statements do not conform to Schedule 14A of the proxy rules promulgated under the Exchange Act. In addition, as a “foreign private issuer,” our officers and directors are exempt from the rules under the Exchange Act relating to short swing profit reporting and liability.

The SEC allows us to “incorporate by reference” into this prospectus the information we file with, and furnish to it, which means that we can disclose important information to you by referring you to those filed or furnished documents. The information incorporated by reference is considered to be a part of this prospectus. However, statements contained in this prospectus or in documents that we file with or furnish to the SEC and that are incorporated by reference into this prospectus will automatically update and supersede information contained in this prospectus, including information in previously filed or furnished documents or reports that have been incorporated by reference into this prospectus, to the extent the new information differs from or is inconsistent with the old information. We hereby incorporate by reference the documents listed below:

We are also incorporating by reference any documents that we file with the SEC after the date of the filing of this registration statement of which the prospectus forms a part and prior to the subsequent effectiveness of that registration statement, and all subsequent annual reports on Form 20-F that we file with the SEC and certain current reports on Form 6-K that we file with or furnish to the SEC pursuant to Section 13(a), 13(c) or 15(d) of the Exchange Act subsequent to the date of this prospectus until we file a post-effective amendment indicating that the offering of the securities made by this prospectus has been terminated.

We will provide without charge to each person, including any beneficial owner, to whom this prospectus is delivered, upon his or her written or oral request, a copy of any or all documents referred to above which have been or may be incorporated by reference into this prospectus. You may obtain a copy of these documents by writing to or telephoning us at the following address: Attn: General Counsel, United Maritime Corporation, 154 Vouliagmenis Avenue, 166 74 Glyfada, Greece, Tel: +30 2130181507. Alternatively, copies of these documents are available via our website (www.unitedmaritime.gr). The information on our website is not incorporated by reference into this prospectus.

The undersigned registrant hereby undertakes:

Pursuant to the requirements of the Securities Act of 1933, the registrant certifies that it has reasonable grounds to believe that it meets all of the requirements for filing on Form F-3 and has duly caused this registration statement to be signed on its behalf by the undersigned, thereunto duly authorized, in the City of Athens, Country of Greece on July 13, 2026.

KNOW ALL PERSONS BY THESE PRESENTS, that each person whose signature appears below constitutes and appoints each of Stamatios Tsantanis and Will Vogel his or her true and lawful attorney-in-fact and agent, with full powers of substitution and resubstitution, for him or her and in his or her name, place and stead, in any and all capacities, to sign any and all amendments (including post-effective amendments) to this registration statement and any and all additional registration statements pursuant to Rule 462(b) of the Securities Act of 1933, as amended, and to file the same, with all exhibits thereto, and all other documents in connection therewith, with the Securities and Exchange Commission, granting unto said attorneys-in-fact and agents full power and authority to do and perform each and every act and thing requisite and necessary to be done, as fully for all intents and purposes as he or she might or could do in person, hereby ratifying and confirming all that said attorneys-in-fact and agents or either of them or their or his or her substitute or substitutes, may lawfully do or cause to be done by virtue thereof.

Pursuant to the requirements of the Securities Act of 1933, this registration statement has been signed by the following persons on July 13, 2026 in the capacities indicated.

Pursuant to the Securities Act of 1933, the undersigned, the duly authorized representative in the United States of United Maritime Corporation, has signed this registration statement in the City of Newark, State of Delaware on July 13, 2026.