This Amendment is being filed solely to provide the financial statements and pro forma financial information required by

Results of Operations and Financial Condition. On June 24, 2026, Worthington Steel, Inc. (“we,” “us,” “our” and “registrant”) issued a news release (“the Original Financial Release”) reporting results for the three months ended May 31, 2026 (the fourth quarter of fiscal 2026). A copy of the news release was furnished as Exhibit 99.1 to a Current Report on Form 8-K filed by the Company on June 25, 2026. Subsequent to the Original Financial Release, we identified and corrected certain errors in…

Creation of a Direct Financial Obligation or an Obligation under an Off-Balance Sheet Arrangement of a Registrant. The information set forth under

Entry into a Material Definitive Agreement. On June 25, 2026, Worthington Steel, Inc. (the “ Company ”) entered into that certain Credit Agreement (the “ Credit Agreement ”), an asset-based revolving credit agreement, among the Company, as borrower, the lenders party thereto, and Wells Fargo Bank, National Association, as agent for the lenders (the “ Agent ”), which refinanced and replaced the Revolving Credit and Security Agreement, dated November 30, 2023 (the “ Former Credit Agreement ”),…

Termination of a Material Definitive Agreement. On June 25, 2026, upon execution of the Credit Agreement, the Company terminated the Former Credit Agreement. The Former Credit Agreement provided for a secured revolving credit facility of up to $550,000,000 plus an uncommitted accordion. The Former Credit Agreement would have matured on November 30, 2028. Upon the termination of the Former Credit Agreement, all security interests granted to the secured parties thereunder were terminated and re…

Corporate Controller and Principal Accounting Officer — Steven R. Witt: Mr. Witt retired from his position as Corporate Controller and Principal Accounting Officer, succeeded by Gwen Joseph.

Other Events. On June 24, 2026, we issued a news release (the “Dividend Release”) reporting that our board of directors declared a quarterly cash dividend of $0.16 per common share. The dividend was declared on June 24, 2026, and is payable on September 29, 2026, to our shareholders of record at the close of business on September 15, 2026. A copy of the Dividend Release is filed herewith as Exhibit 99.3.

Results of Operations and Financial Condition. On June 24, 2026, Worthington Steel, Inc. (“we,” “us,” “our” and “registrant”) issued a news release (the “Original Financial Release”) reporting results for the three months ended May 31, 2026 (the fourth quarter of fiscal 2026). The Original Financial Release included a non-GAAP reconciliation table for EBIT, Adjusted EBIT and Adjusted EBITDA for the three months ended May 31, 2026 and 2025 in which footnote (2) to the table was erroneously dup…

of this Current Report on Form 8-K under the cover of an amendment to this Current Report on Form 8-K no later than 71 calendar days after the date on which this Current Report on Form 8-K was required to be filed. (d) Exhibits. Exhibit No. Document Description 99.1* Press Release, dated June 3, 2026 104 Cover Page Interactive Data File (embedded within the Inline XBRL document) * The information “furnished” in this Current Report on Form 8-K under Item 7.01 (including Exhibit 99.1) shall not…

in this Form 8-K shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), or otherwise subject to the liabilities of that section and shall not be deemed incorporated by reference in any filing made by the Company under the Securities Act of 1933, as amended, or the Exchange Act, except as set forth by specific reference in such filing. Important Information This Current Report on Form 8-K and the materials included herewi…

Regulation FD Disclosure.* Notes Offering On May 26, 2026, the Company issued a press release announcing the commencement of a private offering (the “Notes Offering”) by WS Escrow LLC (the “Escrow Issuer”), a newly formed Delaware limited liability company and wholly owned subsidiary of the Company, of $900,000,000 aggregate principal amount of its senior secured notes due 2033 (the “Notes”). If the Klöckner Acquisition is expected to be consummated within three business days of the closing o…

Other Events. On March 25, 2026, we issued a news release (the “Dividend Release”) reporting that our board of directors declared a quarterly cash dividend of $0.16 per common share. The dividend was declared on March 25, 2026, and is payable on June 26, 2026, to our shareholders of record at the close of business on June 12, 2026. A copy of the Dividend Release is filed herewith as Exhibit 99.3.

Results of Operations and Financial Condition. On March 25, 2026, Worthington Steel, Inc. (“we,” “us,” “our” and “registrant”) issued a news release (the “Financial Release”) reporting results for the three months ended February 28, 2026 (the third quarter of fiscal 2026). A copy of the Financial Release is furnished herewith as Exhibit 99.1 and is incorporated herein by reference. We will host a conference call at 8:30 a.m. ET on March 26, 2026, to discuss our unaudited financial results for…

Entry Into a Material Definitive Agreement. Amendment to Offer Document; Reduction of Minimum Acceptance Threshold On March 10, 2026, Worthington Steel GmbH, a limited liability company established under German law ( Gesellschaft mit beschränkter Haftung ) (“Bidder”), a wholly owned indirect subsidiary of Worthington Steel, Inc., an Ohio corporation (the “Company” or “Worthington Steel”), published an amendment (the “Offer Amendment”) to the offer document, dated February 5, 2026 (the “Offer…

Creation of a Direct Financial Obligation or an Obligation under an Off-Balance Sheet Arrangement of a Registrant. The information set forth above in

Entry Into a Material Definitive Agreement. Business Combination Agreement On January 15, 2026, Worthington Steel, Inc., an Ohio corporation (the “ Company ” or “ Worthington Steel ”), and Worthington Steel GmbH, a limited liability company established under German law ( Gesellschaft mit beschränkter Haftung ) (“ Bidder ”), and Klöckner & Co SE, a European stock corporation ( societas europaea ) organized under the laws of Germany (“ Kloeckner ”), entered into a business combination agreement…

Results of Operations and Financial Condition. On December 17, 2025, Worthington Steel, Inc. (“we,” “us,” “our” and “registrant”) issued a news release (the “Financial Release”) reporting results for the three months ended November 30, 2025 (the second quarter of fiscal 2026). A copy of the Financial Release is furnished herewith as Exhibit 99.1 and is incorporated herein by reference. We conducted a conference call on December 18, 2025, to discuss our unaudited financial results for the seco…

Other Events. On December 17, 2025, we issued a news release (the “Dividend Release”) reporting that our board of directors declared a quarterly cash dividend of $0.16 per common share. The dividend was declared on December 17, 2025, and is payable on March 27, 2026, to our shareholders of record at the close of business on March 13, 2026. A copy of the Dividend Release is filed herewith as Exhibit 99.4.

Results of Operations and Financial Condition. On September 24, 2025, Worthington Steel, Inc. (“we,” “us,” “our” and “registrant”) issued a news release (the “Financial News Release”) reporting results for the three months ended August 31, 2025 (the first quarter of fiscal 2026). A copy of the Financial News Release is furnished herewith as Exhibit 99.1 and is incorporated herein by reference. We conducted a conference call on September 25, 2025, to discuss our unaudited financial results for…

Other Events. On September 24, 2025, we issued a news release (the “Dividend Release”) reporting that our board of directors declared a quarterly cash dividend of $0.16 per common share. The dividend was declared on September 24, 2025, and is payable on December 26, 2025, to our shareholders of record at the close of business on December 12, 2025. A copy of the Dividend Release is filed herewith as Exhibit 99.4.

Other Events. On June 25, 2025, we issued a news release (the “Dividend Release”) reporting that our Board declared a quarterly cash dividend of $0.16 per common share. The dividend was declared on June 25, 2025, and is payable on September 26, 2025, to our shareholders of record at the close of business on September 12, 2025. A copy of the Dividend Release is filed herewith as Exhibit 99.5.

Results of Operations and Financial Condition. On June 25, 2025, Worthington Steel, Inc. (“we,” “us,” “our” and “registrant”) issued a news release (the “Financial News Release”) reporting results for the three months and fiscal year ended May 31, 2025 (the fourth quarter of fiscal 2025). A copy of the Financial News Release is furnished herewith as Exhibit 99.1 and is incorporated herein by reference. We conducted a conference call on June 26, 2025, to discuss our fourth quarter and full yea…

Director — Carl A. Nelson Jr.: The filing reports the planned retirement of a director and the appointment of a new director to fill the vacancy, which is a routine board composition change.

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 hereunto duly authorized. WORTHINGTON STEEL, INC. Date: March 31, 2025 By: /s/ Joseph Y. Heuer Joseph Y. Heuer Vice President - General Counsel and Secretary

Entry into a Material Definitive Agreement. On March 25, 2025, Tempel Canada Company (“Tempel Canada”), a subsidiary of Worthington Steel, Inc. (“we,” “us,” “our” and “registrant”), entered into a letter of offer (“Letter”) with Business Development Bank of Canada (“BDC”). Pursuant to the terms of the Letter, BDC has committed to lend Tempel Canada up to CAD $57,500,000 (“Loan”), subject to the satisfaction of customary closing conditions and deliverables. The purpose of the Loan is to fund t…