The opening hours are now the same for all members. They open at 10am from sunday to friday and saturdays at 9:30am
M-F 10:00am - 8:30pm Sat. 9:30am - 7:00pm Sun. 10:00am - 6:00pm Sat. 11/18 Holiday Hours 9:30am - 7:00pm
Different warehouses have different hours; currently San Leandro Costco is open, to all members, at 0900 hours (9am) Sunday through Saturday. Closed all day on Thanksgiving/christmas/new years day
What David Monterroza said below -same time for all.
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