FORM 6 - K

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

Report of Foreign Private Issuer

Pursuant to Rule 13a - 16 or 15d - 16 of

the Securities Exchange Act of 1934

As of 3/31/2026

Ternium S.A.

(Translation of Registrant's name into English)

Ternium S.A.

26, Boulevard Royal, 4th floor

L-2449 Luxembourg

(352) 2668-3152

(Address of principal executive offices)

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

Form 20-Fa Form 40-F __

Indicate by check mark whether the registrant by furnishing the information contained in this Form is also thereby furnishing the information to the Commission pursuant to Rule 12G3-2(b) under the Securities Exchange Act of 1934.

Yes __ Noa

If “Yes” is marked, indicate below the file number assigned to the registrant in connection with Rule 12g3-2(b):

Not applicable

The attached material is being furnished to the Securities and Exchange Commission pursuant to Rule 13a-16 and Form 6-K under the Securities Exchange Act of 1934, as amended.

This report contains Ternium S.A.’s press release announcing Ternium has filed 2025 Form 20-F.

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, thereunto duly authorized.

TERNIUM S.A.

By: /s/ Guillermo Etchepareborda By: /s/ Sebastián Martí

Name: Guillermo Etchepareborda Name: Sebastián Martí

Title: Attorney in Fact Title: Attorney in Fact

Dated: March 31, 2026

Sebastián Martí

Ternium - Investor Relations

+1 (866) 890 0443

+54 (11) 4018 8389

www.ternium.com

Ternium Files 2025 Form 20-F

Luxembourg, March 31, 2026 – Ternium S.A. (NYSE: TX) announced that it has filed its annual report on Form 20-F, for the year ended December 31, 2025, with the U.S. Securities and Exchange Commission (SEC). The annual report can be downloaded from the SEC’s website at www.sec.gov and from Ternium’s website at www.ternium.com, in the Investors section.

Forward Looking Statements

Some of the statements contained in this press release are “forward-looking statements”. Forward-looking statements are based on management’s current views and assumptions and involve known and unknown risks that could cause actual results, performance or events to differ materially from those expressed or implied by those statements. These risks include but are not limited to risks arising from uncertainties as to gross domestic product, related market demand, global production capacity, tariffs, cyclicality in the industries that purchase steel products and other factors beyond Ternium’s control.

About Ternium

Ternium is a leading steel producer in the Americas, providing advanced steel products to a wide range of manufacturing industries and the construction sector. We invest in low carbon emissions steelmaking technologies to support the energy transition and the mobility of the future. We also support the development of our communities, especially through educational programs in Latin America. More information about Ternium is available at www.ternium.com.

Ternium S.A. 6-K