COST: Other company developments

Item 8.01. Other Events The Board of Directors declared a quarterly cash dividend on the Company's common stock of $1.47 per share. The dividend was declared on October 14, 2026, and is payable November 13, 2026, to shareholders of record at the close of business on October 30, 2026. Item 9.01. Financial Statements and Exhibits (d) Exhibits. 99.1. Press release dated October 14, 2026. 104 Cover Page Interactive Data File (embedded within the Inline XBRL document). SIGNATURE 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. COSTCO WHOLESALE CORPORATION Dated: October 14, 2026 By: /s/ Gary Millerchip Gary Millerchip Executive Vice President and Chief Financial Officer