PATRIOT NATIONAL BANCORP INC

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 10-K

For the fiscal year ended December 31, 2025

OR

Commission file number 000-29599

PATRIOT NATIONAL BANCORP, INC.

(Exact name of registrant as specified in its charter)

(Registrant’s telephone number, including area code) (203)252-5900

Securities registered under Section 12(b) of the Exchange Act:

Securities registered under Section 12(g) of the Exchange Act: None

Indicate by check mark if the registrant in a well-known seasoned issuer, as defined in Rule 405 of the Securities Act of 1933. Yeso No x

Indicate by check mark if the registrant is not required to file reports pursuant to Section 13 of 15(d) of the Securities Exchange Act of 1934. Yeso No x

Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the past 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days: Yes x Noo

Indicate by check mark whether the registrant has submitted electronically every Interactive Data File required to be submitted pursuant to Rule 405 of Regulation S-T (§232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit such files). Yes x Noo

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company, or an emerging growth company. See the definitions of “large accelerated filer,” “accelerated filer,” “smaller reporting company,” and “emerging growth company” in Rule 12b-2 of the Exchange Act

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. o

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

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

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

Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act). Yeso Nox

As of June 30, 2025, the aggregate market value of the voting stock held by non-affiliates of the registrant based on the last sale price on June 30, 2025 as reported on the NASDAQ Global Market: $71.2 million.

Number of shares of the registrant’s Common stock, $0.01 par value per share,117,085,713 shares outstanding as of March 31, 2026.

Document Incorporated by Reference

Portions of a Definitive Proxy Statement for the registrant's 2026 Annual Meeting of Shareholders, which will be filed with the Securities and Exchange Commission within 120 days after the close of the fiscal year covered by this Form 10-K, are incorporated into Part III of this Form 10-K.

PATRIOT NATIONAL BANCORP, INC.

ANNUAL REPORT ON FORM 10-K

For the Year Ended December 31, 2025

TABLE OF CONTENTS