Up to $150,000,000 Common Stock We have entered into a sales agreement, dated May 6, 2026 (the “Sales Agreement”), with Roth Capital Partners, LLC as leadagent (Roth or the “Lead Agent”) and USCA Securities LLC (“USCA”) (each of Roth and USCA, an “Agent” and together, the“Agents”), relating to shares of our common stock offered by this prospectus supplement and the accompanying prospectus. Inaccordance with the terms of the Sales Agreement, we may offer and sell shares of our common stock from time to time throughthe Lead Agent. This prospectus supplement is offering shares of our common stock having an aggregate offering price of $150million. Shares of our common stock trade on the Nasdaq Global Market (“Nasdaq”), under the symbol “HPK.” On May 5, 2026, the lastsale price of the shares as reported on Nasdaq was $6.79 per share. Sales of our common stock, if any, pursuant to this prospectus supplement and the accompanying prospectus will be made in anymethod permitted by law deemed to be an “at the market offering” as defined in Rule 415 under the Securities Act of 1933, asamended (the “Securities Act”). The Lead Agent will make all sales using commercially reasonable efforts consistent with itsnormal sales and trading practices on terms mutually agreed upon between Lead Agent and us. The compensation to the Agents for sales of our common stock pursuant to the Sales Agreement will be an amount up to 3.00% ofthe gross sales price of all common stock sold thereunder. In connection with the sale of the common stock on our behalf, theAgents will be deemed to be an “underwriter” within the meaning of the Securities Act, and the compensation of the Agents will bedeemed to be underwriting commissions or discounts. We have also agreed to provide indemnification and contribution to theAgents with respect to certain liabilities, including liabilities under the Securities Act or the Securities Exchange Act of 1934, asamended (the “Exchange Act”). Investing in our common stock involves risks. See“Risk Factors”beginning on page S-3 of this prospectus supplement andon page 2 of the accompanying prospectus for information regarding risks you should consider before investing in ourcommon stock. Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of thesesecurities or determined if this prospectus supplement or the accompanying prospectus is truthful or complete. Anyrepresentation to the contrary is a criminal offense. USCA Securities Roth Capital Partners TABLE OF CONTENTS Prospectus Supplement ABOUT THIS PROSPECTUS SUPPLEMENTS-iiiCAUTIONARY STATEMENT REGARDING FORWARD-LOOKING STATEMENTSS-ivSUMMARYS-1THE OFFERINGS-2RISK FACTORSS-3USE OF PROCEEDSS-4PLAN OF DISTRIBUTIONS-5MATERIAL U.S. FEDERAL INCOME TAX CONSIDERATIONS FOR NON-U.S. HOLDERSS-6LEGAL MATTERSS-10EXPERTSS-10WHERE YOU CAN FIND MORE INFORMATIONS-10DOCUMENTS INCORPORATED BY REFERENCES-10 Base Prospectus ABOUT THIS PROSPECTUSiiWHERE YOU CAN FIND MORE INFORMATIONiiiDOCUMENTS INCORPORATED BY REFERENCE1CAUTIONARY NOTE REGARDING FORWARD-LOOKING STATEMENTS2ABOUT HIGHPEAK ENERGY, INC.4RISK FACTORS5USE OF PROCEEDS6DESCRIPTION OF SECURITIES7PLAN OF DISTRIBUTION10LEGAL MATTERS12EXPERTS12 Resale Prospectus ABOUT THIS PROSPECTUSiiWHERE YOU CAN FIND MORE INFORMATIONiiiDOCUMENTS INCORPORATED BY REFERENCE1CAUTIONARY NOTE REGARDING FORWARD-LOOKING STATEMENTS2ABOUT HIGHPEAK ENERGY, INC.4RISK FACTORS5USE OF PROCEEDS6DESCRIPTION OF SECURITIES7SELLING SECURITYHOLDERS10PLAN OF DISTRIBUTION12LEGAL MATTERS15EXPERTS15 ABOUT THIS PROSPECTUS SUPPLEMENT This document is in two parts. The first part, the prospectus supplement, including the documents incorporated by referencetherein, describes the specific terms of this offering and certain matters relating to us. The second part, the accompanyingprospectus, including the documents incorporated by reference therein, provides more general information, some of which may notapply to this offering. The accompanying prospectus was filed as part of our registration statement on Form S-3 (Registration No.333-291266) with the Securities and Exchange Commission (the “SEC”) on November 4, 2025, as part of a “shelf” registrationprocess and became effective on November 25, 2025. Under the shelf registration process, we may sell our common stock in oneor more offerings. Generally, when we refer to this prospectus supplement, we are referring to both parts of this documentcombined. We urge you to read carefully this prospectus supplement, the accompanying prospectus, the information incorporatedby reference herein and therein, and any free writing prospectus that we authorize to be distributed to you before buying ourcommon stock being offered under this prospectus supplement. This prospectus supplement may supplement, update or changeinformation contained in the accompanying prospectus. To the extent that any statement that we make in this prospectussupplement is inconsistent with




