U.S. 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 October 2025

Nexa Resources S.A.

(Exact Name as Specified in its Charter)

N/A

(Translation of Registrant’s Name)

37A, Avenue J.F. Kennedy
L-1855, Luxembourg
Grand Duchy of Luxembourg
(Address of principal executive offices)

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

Form 20-F X

Form 40-F

Indicate by check mark if the registrant is submitting the Form 6-K in paper as permitted by Regulation S-T Rule 101(b)(1): ____

Indicate by check mark if the registrant is submitting the Form 6-K in paper as permitted by Regulation S-T Rule 101(b)(7): ____

Indicate by check mark whether by furnishing the information contained in this Form, the registrant is also thereby furnishing the information to the Commission pursuant to Rule 12g3-2(b) under the Securities Exchange Act of 1934.

Yes

No X

If “Yes” is marked, indicate below the file number assigned to the registrant in connection with Rule 12g3-2(b): Not applicable.

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: October 30, 2025

Nexa Resources S.A.

By:/s/ José Carlos del Valle

Name: José Carlos del Valle

Title: Senior Vice President of Finance and Group Chief Financial Officer

EXHIBIT INDEX

Exhibit

Description of Exhibit

99.1

99.2

Nexa 3Q25 - Interim CEO Certification

Nexa 3Q25 - Interim CFO Certification

Nexa Resources S.A. 6-K