6-K

UNITED STATES

SECURITIES AND EXCHANGECOMMISSION

Washington, D.C. 20549

FORM 6-K

Report of Foreign Private Issuer

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

Securities Exchange Act of 1934

For the month of December2023

Commission File Number1-14732

COMPANHIA SIDERÚRGICANACIONAL

(Exact name of registrantas specified in its charter)

National Steel Company

(Translation of registrant’sname into English)

Av. Brigadeiro Faria Lima3400, 20th FloorSão Paulo, SP, Brazil04538-132

(Address of principal executiveoffice)

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 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 _______ No ___X____

Announcement of Expiration of Tender Offer for Any and All 2026 Notesby CSN Resources S.A.

São Paulo, December 5, 2023 – Companhia SiderúrgicaNacional (“CSN”) (NYSE: SID) announced today that the cash tender offer (the “Tender Offer”) by its subsidiary, CSN Resources S.A. (“CSN Resources”), for any and all of its outstanding US$300,000,000 in aggregate principal amount of 7.625% Senior Unsecured Guaranteed Notes due 2026 (the “Notes”) (144A CUSIP / ISIN: 12644VAC2 / US12644VAC28 and Regulation S CUSIP / ISIN: L21779AD2 / USL21779AD28), fully, unconditionally and irrevocably guaranteed by CSN, expired today at 5:00 p.m., New York City time (the “Expiration Time”). At the Expiration Time, valid tenders had been received with respect to US$117,021,000 in aggregate principal amount of Notes.

CSN Resources expects to accept and make payment for all validly tendered Notes at or prior to the Expiration Time on December 8, 2023.

Holders of Notes who validly tendered their Notes at or prior to the Expiration Time are eligible to receive US$1,010 per US$1,000 principal amount of Notes. In addition, accrued and unpaid interest from the last interest payment date to, but not including, the settlement date for the Notes will be paid in cash on all validly tendered and accepted Notes.

Disclaimer

This press release is for informational purposes only and does not constitute an offer to purchase or the solicitation of an offer to sell any securities.

This press release may contain forward-looking statements within the meaning of Section 27A of the U.S. Securities Act of 1933, as amended, and Section 21E of the U.S. Securities Exchange Act of 1934, as amended, including those related to the Tender Offer. Forward-looking information involves important risks and uncertainties that could significantly affect anticipated results in the future, and, accordingly, such results may differ from those expressed in any forward-looking statements.

COMPANHIA SIDERÚRGICANACIONAL

Marcelo Cunha Ribeiro

Chief Financial and InvestorRelations Officer

SIGNATURES

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