Summary of Significant Accounting Policies	6 Months Ended
Feb. 15, 2026
Accounting Policies [Abstract]
Summary of Significant Policies	Note 1—Summary of Significant Accounting Policies Description of Business Costco Wholesale Corporation (Costco or the Company), a Washington corporation, and its subsidiaries operate membership warehouses based on the concept that offering members low prices on a limited selection of nationally-branded and private-label products in a wide range of merchandise categories will produce high sales volumes and rapid inventory turnover. At February 15, 2026, Costco operated 924 warehouses worldwide: 634 in the United States (U.S.) located in 47 states, Washington, D.C., and Puerto Rico, 114 in Canada, 42 in Mexico, 37 in Japan, 29 in the United Kingdom (U.K.), 20 in Korea, 15 in Australia, 14 in Taiwan, seven in China, five in Spain, three in France, two in Sweden and one each in Iceland and New Zealand. The Company operates e-commerce sites in the U.S., Canada, the U.K., Mexico, Korea, Taiwan, Japan, and Australia. Basis of Presentation The condensed consolidated financial statements include the accounts of Costco and its wholly-owned subsidiaries. All material inter-company transactions among the Company and its consolidated subsidiaries have been eliminated in consolidation. These unaudited condensed consolidated financial statements have been prepared in accordance with the instructions to Form 10-Q for interim financial reporting pursuant to the rules and regulations of the Securities and Exchange Commission (SEC). While these statements reflect all normal recurring adjustments that are, in the opinion of management, necessary for fair presentation of the results of the interim period, they do not include all of the information and footnotes required by U.S. generally accepted accounting principles (U.S. GAAP) for complete financial statements. Therefore, the interim condensed consolidated financial statements should be read in conjunction with the consolidated financial statements and notes included in the Company's Annual Report on Form 10-K for the fiscal year ended August 31, 2025. Fiscal Year End The Company operates on a 52/53 week fiscal year basis, with the fiscal year ending on the Sunday closest to August 31. Fiscal 2026 is a 52-week year ending on August 30, 2026. References to the second quarter of 2026 and 2025 relate to the 12-week fiscal quarters ended February 15, 2026, and February 16, 2025. References to the first half of 2026 and 2025 relate to the 24 weeks ended February 15, 2026, and February 16, 2025. Use of Estimates The preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect: the reported amounts of assets and liabilities and the disclosure of contingent assets and liabilities at the date of the financial statements; and the reported amounts of revenues and expenses during the reporting period. These estimates and assumptions take into account historical and forward-looking factors that the Company believes are reasonable. Actual results could differ from those estimates and assumptions. Recent Accounting Pronouncements Not Yet Adopted By The Company In December 2023, the Financial Accounting Standards Board (FASB) issued ASU 2023-09, which requires public business entities on an annual basis to disclose specific categories in the income-tax rate reconciliation, provide information for reconciling items that meet a quantitative threshold, and disclose certain information about income taxes paid. The standard is effective for annual periods beginning after December 15, 2024, with early adoption permitted. In November 2024, the FASB issued ASU 2024-03, which requires disaggregated disclosures of certain costs and expenses on the income statement on an annual and interim basis. The standard is effective for fiscal years beginning after December 15, 2026, and interim periods within fiscal years beginning after December 15, 2027, with early adoption permitted. These standards should be applied on a prospective basis. Retrospective application is permitted. The Company is evaluating these standards.

Costco Wholesale Corporation (Costco or the Company), a Washington corporation, and its subsidiaries operate membership warehouses based on the concept that offering members low prices on a limited selection of nationally-branded and private-label products in a wide range of merchandise categories will produce high sales volumes and rapid inventory turnover. At February 15, 2026, Costco operated 924 warehouses worldwide: 634 in the United States (U.S.) located in 47 states, Washington, D.C., and Puerto Rico, 114 in Canada, 42 in Mexico, 37 in Japan, 29 in the United Kingdom (U.K.), 20 in Korea, 15 in Australia, 14 in Taiwan, seven in China, five in Spain, three in France, two in Sweden and one each in Iceland and New Zealand. The Company operates e-commerce sites in the U.S., Canada, the U.K., Mexico, Korea, Taiwan, Japan, and Australia.

The condensed consolidated financial statements include the accounts of Costco and its wholly-owned subsidiaries. All material inter-company transactions among the Company and its consolidated subsidiaries have been eliminated in consolidation.

These unaudited condensed consolidated financial statements have been prepared in accordance with the instructions to Form 10-Q for interim financial reporting pursuant to the rules and regulations of the Securities and Exchange Commission (SEC). While these statements reflect all normal recurring adjustments that are, in the opinion of management, necessary for fair presentation of the results of the interim period, they do not include all of the information and footnotes required by U.S. generally accepted accounting principles (U.S. GAAP) for complete financial statements. Therefore, the interim condensed consolidated financial statements should be read in conjunction with the consolidated financial statements and notes included in the Company's Annual Report on Form 10-K for the fiscal year ended August 31, 2025.

The Company operates on a 52/53 week fiscal year basis, with the fiscal year ending on the Sunday closest to August 31. Fiscal 2026 is a 52-week year ending on August 30, 2026. References to the second quarter of 2026 and 2025 relate to the 12-week fiscal quarters ended February 15, 2026, and February 16, 2025. References to the first half of 2026 and 2025 relate to the 24 weeks ended February 15, 2026, and February 16, 2025.

The preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect: the reported amounts of assets and liabilities and the disclosure of contingent assets and liabilities at the date of the financial statements; and the reported amounts of revenues and expenses during the reporting period. These estimates and assumptions take into account historical and forward-looking factors that the Company believes are reasonable. Actual results could differ from those estimates and assumptions.

In December 2023, the Financial Accounting Standards Board (FASB) issued ASU 2023-09, which requires public business entities on an annual basis to disclose specific categories in the income-tax rate reconciliation, provide information for reconciling items that meet a quantitative threshold, and disclose

In November 2024, the FASB issued ASU 2024-03, which requires disaggregated disclosures of certain costs and expenses on the income statement on an annual and interim basis. The standard is effective for fiscal years beginning after December 15, 2026, and interim periods within fiscal years beginning after December 15, 2027, with early adoption permitted.