Subsidiaries

State or Other Jurisdiction of
Incorporation or Organization

Name under Which Subsidiary
Does Business

Costco Canada Holdings Inc.

Canadian Federal

Costco Canada Holdings Inc.

Costco Wholesale Membership, Inc.

California

Costco Wholesale Membership, Inc.

Costco Wholesale United Kingdom Ltd.

United Kingdom

Costco Wholesale United
Kingdom Ltd.

Costco Wholesale Canada Ltd.

Canadian Federal

Costco Wholesale Canada, Ltd., Costco Wholesale

NW Re Ltd.

Arizona

NW Re Ltd.

PriceCostco International, Inc.

Nevada

PriceCostco International, Inc.

Costco Wholesale Korea, Ltd.

Korea

Costco Wholesale Korea, Ltd.

Costco de Mexico, S.A. de C.V.

Mexico

Costco de Mexico, S.A. de C.V.