COST: Financial results

Item 2.02. Results of Operations and Financial Condition On May 28, 2026, the Company issued a press release containing its operating results for the third quarter (twelve weeks) and the first 36 weeks of fiscal 2026, ended May 10, 2026. A copy of the press release is attached as Exhibit 99.1. In addition, a copy of the Company's earnings release supplement for the third quarter of fiscal 2026 is attached as Exhibit 99.2. Item 9.01. Financial Statements and Exhibits (d) Exhibits. 99.1. Press release dated May 28, 2026. 99.2. Third quarter fiscal 2026 supplemental information. 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: May 28, 2026 By: /s/ Gary Millerchip Gary Millerchip Executive Vice President and Chief Financial Officer