Costco official phone number
Find the official Costco phone number listed for Membership and warehouse support. Confirm the company's source page before sharing information or starting a call.
Public U.S. number listed on the source
1-800-774-2678
This number was visible on the linked official source when it was checked on October 17, 2026. Phone numbers and departments can change, so use the source link below to confirm it before calling. A source check cannot establish who is calling you.
Open Costco official sourceSource and department details
- Department or route
- Membership and warehouse support
- Source checked
- October 17, 2026
- Latest listing review
- October 17, 2026 — phone confirmed on the official source.
Evidence from the official source
Membership and Warehouse — 1-800-774-2678. Phone Hours: Mon - Fri: 6am - 6pm PT; Sat - Sun: 8am - 5pm PT.
For membership and warehouse questions. Online order support uses a separate number. For a specific pharmacy or tire center, use Costco's warehouse locator.
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