Yes it's open on Sunday
Monday–Friday: 6 a.m.–9:00 p.m. Saturday: 6 a.m.–7 p.m. Sunday: 6 a.m.–7 p.m. Hours of operation can vary by location, so please consult our location finder to determine your local station's operating hours. For example, in Woodinville WA, the gas station is open 1 hour after closing. Next time Google "Costco gas station hours" and the results pop right up!
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