If you want to know if your store is open these days, you can contact it.
These opening hours don't take account of public holidays and of Sundays. You can also check if Costco Billings is open on lundi by calling it.
Usually Costco Billings is closed on Sundays. Careful, stores-locator.com is a participative site, where anyone can indicate opening hours. If you see any mistake, please contact us.