Costco Wholesale Corporation Reports March Sales Results

ISSAQUAH, WA--(Marketwire - April 9, 2009) - Costco Wholesale Corporation ("Costco") (NASDAQ: COST) today reported net sales of $6.39 billion for the month of March, the five weeks ended April 5, 2009, a decrease of three percent from $6.57 billion in the same five-week period last year. This year's five-week period included 35 days of sales compared to 34 last year, reflecting the timing of Easter. This calendar shift positively impacted this year's total and comparable sales by approximately one to two percent.

For the first thirty-one weeks of its reporting period ended April 5, 2009, the Company reported net sales of $41.47 billion, compared to $41.34 billion during the similar thirty-one-week period last year.

Comparable sales for the five-week retail-reporting month of March and the thirty-one-week retail-reporting period of September through March, both ended April 5, 2009, were as follows:

                                  5 Weeks     31 Weeks
                                  -------     --------
     U.S.                              -2%           0%
     International                    -13%         -10%
     
     Total                             -5%          -2%
                                  =======     ========

Comparable sales for the five-week and thirty-one week periods, excluding the negative impacts from gasoline deflation and foreign exchange (primarily in Canada, the United Kingdom and Korea), were as follows:

                                  5 Weeks     31 Weeks
                                  -------     --------
     U.S. (w/o gas deflation)          +3%          +3%
     International (w/o Fx)            +9%          +8%
     
     Total                             +4%          +4%
                                  =======     ========

Additional discussion of these sales results is available on a pre-recorded telephone message. You can access the recording by dialing 1-800-642-1687 (conference ID 75872886). This recorded message will be available today through 5:00 p.m. (PT) on Friday, April 10, 2009.

Costco currently operates 555 warehouses, including 408 in the United States and Puerto Rico, 76 in Canada, 21 in the United Kingdom, six in Korea, five in Taiwan, eight in Japan and 31 in Mexico. The Company also operates Costco Online, an electronic commerce web site, at www.costco.com and at www.costco.ca in Canada. The Company plans to open an additional seven new warehouses prior to the end of its 2009 fiscal year on August 30, 2009.

Certain statements contained in this document and the pre-recorded telephone message constitute forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995. For these purposes, forward-looking statements are statements that address activities, events, conditions or developments that the Company expects or anticipates may occur in the future. Such forward-looking statements involve risks and uncertainties that may cause actual events, results or performance to differ materially from those indicated by such statements. These risks and uncertainties include, but are not limited to, domestic and international economic conditions including exchange rates, the effects of competition and regulation, uncertainties in the financial markets, consumer and small business spending patterns and debt levels, conditions affecting the acquisition, development, ownership or use of real estate, actions of vendors, rising costs associated with employees (including health care and workers' compensation costs), rising costs associated with the acquisition of merchandise (including the direct and indirect effects of the rising cost of petroleum-based products and fuel and energy costs), geopolitical conditions and other risks identified from time to time in the Company's public statements and reports filed with the Securities and Exchange Commission.

Contact Information: CONTACTS: Costco Wholesale Corporation Richard Galanti 425/313-8203 Jeff Elliott 425/313-8264