Texas Ventures Acquisition III Corp (0002033991) (Filer)

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934

Date of Report (Date of earliest event reported): October 20, 2026

Texas Ventures Acquisition III Corp

(Exact name of Registrant as Specified in Its Charter)

Registrant’s Telephone Number, Including Area Code: (201) 985-8300

N/A

(Former Name or Former Address, if Changed Since Last Report)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

Securities registered pursuant to Section 12(b) of the Act:

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter).

Emerging growth company x

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. ¨

Non-Convertible Promissory Note

As previously disclosed in the Current Report on Form 8-K filed by Texas Ventures Acquisition III Corp (the “Company”) with the Securities and Exchange Commission on October 20, 2026, on October 19, 2026, the shareholders of the Company approved the extension on a monthly basis of the date by which the Company must consummate a business combination from October 24, 2026 up to July 24, 2027 (the date that is 27 months from the closing date of the Company’s initial public offering (the “IPO”)) (the “Extension”). Pursuant to the terms of the Extension, for each monthly extension, the Company is required to deposit $145,000 (each such deposit, an “Extension Payment”) into the trust account with Continental Stock Transfer & Trust Company established in connection with the IPO (the “Trust Account”) no later than two business days prior to the 24th day of each applicable month.

On October 20, 2026, the Company issued a non-convertible promissory note (the “Non-Convertible Note”) in the aggregate principal amount of $145,000 to Yorkville Acquisition Sponsor II, LLC, a Florida limited liability company (the “Sponsor”), in exchange for the Sponsor’s funding of $145,000 to the Company. On October 21, 2026, the Company deposited the $145,000 principal amount of the Non-Convertible Note into the Trust Account as the first monthly Extension Payment, extending the date by which the Company must consummate a business combination to November 24, 2026.

Pursuant to the terms of the Non-Convertible Note, the principal balance shall not accrue interest and shall be payable by the Company on the earlier of the date on which the Company consummates its initial business combination or the date that the winding up of the Company is effective.

The foregoing description of the Non-Convertible Note does not purport to be complete and is qualified in its entirety by reference to the full text of the Non-Convertible Note, which is filed herewith as Exhibit 10.1 and is incorporated herein by reference.

The information disclosed under Item 1.01 of this Current Report on Form 8-K is incorporated by reference into this Item 2.03.

(d) Exhibits.

SIGNATURE

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 hereunto duly authorized.

Date: October 21, 2026