Costco Wholesale Corporation Reports April Sales Results.

Business Editors

ISSAQUAH, Wash.--(BUSINESS WIRE)--May 9, 2002

Costco Wholesale Corporation ("Costco" or the "Company") (Nasdaq: COST) today reported net sales of $2.84 billion for the four weeks ended May 5, 2002, an increase of 11 percent from $2.57 billion in the same four-week period of the prior fiscal year. For the first thirty-five weeks of its 2002 fiscal year ended May 5, 2002, the Company reported net sales of $25.20 billion, an increase of 12 percent from $22.55 billion during the comparable period of the prior fiscal year.

Comparable sales for the 4-week and 35-week periods ended May 5, 2002 were as follows:

                           4 Weeks          35 Weeks
                        --------------    --------------
US                           6%                7%
International                6%                1%

Total Company                6%                6%
                        ==============    ==============

Costco currently operates 389 warehouses, including 285 in the United States, 60 in Canada, 14 in the United Kingdom, five in Korea, three in Taiwan, two in Japan and 20 in Mexico. The Company also operates Costco Online, an electronic commerce web site, at www.costco.com. The Company plans to open seven to eight additional new warehouses (including the relocation of two to three warehouses to larger and better-located facilities) prior to the end of its fiscal year ending September 1, 2002.