ARMSTRONG WORLD INDUSTRIES INC 10-Q

ITEM 2. UNREGISTERED SALES OF EQUITY SECURITIES AND USE OF PROCEEDS (c) Issuer Purchases of Equity Securities Period Total Number of Shares Purchased (1) Average Price Paid per Share Total Number of Shares Purchased as Part of Publicly Announced Plans or Programs Maximum Approximate Value of Shares that may yet be Purchased under the Plans or Programs January 1-31, 2026 61,359 $ 194.05 61,017 $ 520,948,349 February 1-28, 2026 78,299 $ 182.57 55,391 $ 510,668,138 March 1-31, 2026 224,268 $ 168.73 224,268 $ 472,828,500 Total 363,926 340,676 (1) Includes shares reacquired through the withholding of shares to pay employee tax obligations upon the exercise of options or vesting of restricted shares previously granted under our long-term incentive plans. On July 29, 2016, our Board of Directors approved a share repurchase program authorizing us to repurchase up to $150.0 million of our outstanding shares of common stock (the “Program”). Since inception of the Program, this authorization has been increased to permit repurchases of up to an aggregate of $1,700.0 million of our outstanding shares of common stock through December 31, 2026. Repurchases of our common stock under the Program may be made through open market, block and privately negotiated transactions, including Rule 10b5-1 plans, at such times and in such amounts as management deems appropriate, subject to market and business conditions, regulatory requirements and other factors. The Program does not obligate AWI to repurchase any particular amount of common stock and may be suspended or discontinued at any time without notice. During the three months ended March 31, 2026, we repurchased 0.3 million shares under the Program for a total cost of $60.0 million, excluding commissions and taxes, or an average price of $176.00 per share. Since inception through March 31, 2026, we have repurchased 15.7 million shares under the Program for a total cost of $1,227.2 million, excluding commissions and taxes, or an average price of $77.89 per share. ITEM 3. DEFAULTS U PON SENIOR SECURITIES None. ITEM 4. MINE S AFETY DISCLOSURES Not Applicable. ITEM 5. OTHER I NFORMATION Trading Arrangements of Directors and Executive Officers During the three months ended March 31, 2026 , no director or officer of the Company adopted or terminated a “Rule 10b5-1 trading arrangement” or “non-Rule 10b5-1 trading arrangement,” as each term is defined in Item 408(a) of Regulation S-K. 32 ITEM 6. EXHIBITS The following exhibits are filed as part of this Quarterly Report on Form 10-Q: Exhibit No. Description 31.1 Certification of Chief Executive Officer required by Rule 13a-14(a) or 15d-14(a) of the Securities Exchange Act. † 31.2 Certification of Chief Financial Officer required by Rule 13a-14(a) or 15d-14(a) of the Securities Exchange Act. † 32.1 Certification of Chief Executive Officer required by Rule 13a and 18 U.S.C. Section 1350. † † 32.2 Certification of Chief Financial Officer required by Rule 13a and 18 U.S.C. Section 1350. †† 101.INS Inline XBRL Instance Document – the instance document does not appear in the Interactive Data File because its XBRL tags are embedded within the Inline XBRL document. † 101.SCH Inline XBRL Taxonomy Extension Schema With Embedded Linkbase Documents. † 104 The cover page from the Company’s Quarterly Report on Form 10-Q for the quarter ended March 31, 2026 has been formatted in Inline XBRL. † Filed herewith. †† Furnished herewith. 33 SIGNA TURES 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. Armstrong World Industries, Inc. By: /s/ Christopher P. Calzaretta Christopher P. Calzaretta Senior Vice President and Chief Financial Officer (Principal Financial Officer) By: /s/ James T. Burge James T. Burge Vice President and Controller (Principal Accounting Officer) Date: April 28, 2026 34