GGB 6-K
Gerdau S.A. (GGB)
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
SECURITIESEXCHANGE ACT OF 1934
Dated July 20, 2026
Commission File Number 1-14878
GERDAU S.A.
(Translation of Registrant’s Name into English)
Av. Dra. Ruth Cardoso, 8,501 – 8° andar
São Paulo, São Paulo - Brazil CEP 05425-070
(Address of principal executive offices)
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 x Form 40-F ¨
Exhibit Index
| Exhibit | Description of Exhibit |
|---|---|
| 99.1 | Notice to the Market – Closing of the Acquisition of Equity Stake |
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: July 20, 2026
| GERDAU S.A. | |
|---|---|
| By: | /s/ Rafael Dorneles Japur |
| Name: | Rafael Dorneles Japur |
| Title: | Vice-President and Investor Relations Officer |
Exhibit 99.1
GERDAU S.A.
Corporate Tax ID (CNPJ/MF): 33.611.500/0001-19****Registry (NIRE): 35300520696
NOTICETO THE MARKET
Gerdau S.A. (B3: GGBR / NYSE: GGB) (“Company”), further to the Notice to the Market disclosed on April 16, 2026, informs its shareholders and the market in general that it has concluded, on this date, the acquisition of the entire equity stake in Dona Francisca Energética S.A. (“DFESA”), corresponding to 23.03% of its share capital, held by Centrais Elétricas de Santa Catarina S.A. (“CELESC”).
The transaction closed following the satisfaction of the applicable conditions precedent, including approval by the Brazilian antitrust authority. The acquisition was completed at an enterprise value of R$150 million. Including the proportional consolidated cash balance of R$3,909,192.64, the Company made a total cash disbursement of approximately R$154 million, fully paid in cash with its own available resources.
The acquisition is aligned with Gerdau’s capital allocation discipline, contributing to increased competitiveness in its cost structure through the expansion of renewable energy self-production, in line with the Company’s previously disclosed decarbonization strategy.
São Paulo, July 20, 2026.
Rafael Dorneles Japur
Vice-President and
Investor Relations Officer