UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 6-K

REPORT OF FOREIGN PRIVATE ISSUER

PURSUANT TO RULE 13a-16 OR 15d-16 UNDER THE

SECURITIES EXCHANGE ACT OF 1934

For the month of September 2025

Commission File Number: 001-41639

SMX (SECURITY MATTERS) PUBLIC LIMITED COMPANY

(Exact Name of Registrant as Specified in Charter)

Mespil Business Centre, Mespil House

Sussex Road, Dublin 4, Ireland

Tel: +353-1-920-1000

(Address of Principal Executive Offices) (Zip Code)

Indicate by check mark whether the registrant files or will file annual reports under cover of Form 20-F or Form 40-F. Form 20-F ☒ Form 40-F ☐

SMX (Security Matters) Public Limited Company (the “Company”) further amended its 2022 Incentive Equity Plan, as amended (the “Incentive Plan”), to increase the number of authorized Ordinary Shares under the Incentive Plan from approximately 7.8 million to 10,945,354 (the “Amendment”). As a Foreign Private Issuer, Nasdaq Rule 5615(a)(3) allows the Company to rely on home country corporate governance practices in lieu of certain of the rules in the Nasdaq Rule 5600 Series and Rule 5250(d) and, accordingly, the Company so elected to approve the Amendment without stockholder approval. Thereafter, the Company granted an aggregate of 1,750,000 restricted stock units and 1,400,000 stock options to its executive officers and directors, and to certain consultants, employees and advisors to the Company.

As of the close of market on September 9, 2025, the Company had 10,958,624 ordinary shares, par value $0.000000000000287, issued and outstanding. Of such shares, 4,909,188 were issued since August 26, 2025, pursuant to conversions of outstanding convertible promissory notes of the Company.

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the Registrant has duly caused this report to be signed on its behalf by the undersigned thereunto duly authorized.

Date: September 10, 2025