Note 1 - Organization	12 Months Ended
Sep. 30, 2025
Notes to Financial Statements
Nature of Operations [Text Block]	1. Organization Nature of Business Natural Grocers by Vitamin Cottage, Inc. (Natural Grocers or the holding company) and its consolidated subsidiaries (collectively, the Company) operate retail stores that specialize in natural and organic groceries, dietary supplements and body care products. The Company operated 169 retail stores as of September 30, 2025, including 45 stores in Colorado, 25 in Texas, 14 in Oregon, 11 in Arizona, eight in each of Kansas and Utah, seven in Missouri, six in each of Idaho, Iowa, New Mexico and Oklahoma, five in Washington, four in each of Montana and Nevada, three in each of Arkansas, Nebraska and North Dakota, two in Wyoming, and one in each of Louisiana, Minnesota, and South Dakota. The Company also has a bulk food repackaging facility and distribution center in Golden, Colorado. The Company had 169 stores as of September 30, 2024.

The entire disclosure for the nature of an entity's business, major products or services, principal markets including location, and the relative importance of its operations in each business and the basis for the determination, including but not limited to, assets, revenues, or earnings. For an entity that has not commenced principal operations, disclosures about the risks and uncertainties related to the activities in which the entity is currently engaged and an understanding of what those activities are being directed toward.

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