Amendment to Annual Report (Form 10-K/A)

Horizon Technology Finance Corporation, or the Company, which may also be referred to as "we," "us" or "our," is filing this Amendment No. 1 (the "Amendment") to its Annual Report on Form 10-K for the Company's fiscal year ended December 31, 2025, as originally filed with the Securities and Exchange Commission (the "SEC") on March 3, 2026 (the "Original Report"). The purpose of this Amendment is to include Part III information, which was intended to be incorporated by reference from the Company's definitive proxy statement for the 2026 Annual Meeting of Stockholders. This information was previously omitted from the Original Report in reliance on General Instruction G(3) to Form 10-K, which would permit the Part III information to be incorporated in the Original Report by reference from the Company's definitive proxy statement if such proxy statement were filed no later than 120 days after the fiscal year-end. The Company is filing this Amendment to include the Part III information in the Annual Report on Form 10-K for the year ended December 31, 2025 because a definitive proxy statement containing such information will not be filed by the Company within 120 days after the end of the fiscal year covered by the Original Report. This Amendment also updates, amends and supplements Part III and Part IV, including Item 15 of the Form 10-K. Item 15 of Part IV has been amended to include new certifications pursuant to Section 302 of the Sarbanes-Oxley Act of 2002 by our principal executive officer and principal financial officer as required by Rule 12b-15 under the Securities Exchange Act of 1934, as amended (the "Exchange Act"). Because no financial statements have been included in this Amendment and this Amendment does not contain or amend any disclosure with respect to Items 307 and 308 of Regulation S-K, paragraphs 3, 4, and 5 of the certifications have been omitted. The certifications pursuant to Section 302 of the Sarbanes-Oxley Act of 2002 of our principal executive officer and principal financial officer are filed with this Amendment as Exhibits 31.3 and 31.4 hereto. In addition, the cover page has been updated and amended.

The Amendment does not affect any other items in the Original Report, including the Company's financial statements and the notes to the financial statements. Except as otherwise indicated, the Amendment speaks as of the date of the Original Report and reflects only the changes discussed above. Accordingly, this Amendment should be read in conjunction with the Original Report.