Costco Wholesale Corporation Reports November Sales

ISSAQUAH, WA -- (MARKET WIRE) -- November 30, 2006 -- Costco Wholesale Corporation ("Costco") (NASDAQ: COST) today reported net sales of $4.84 billion for the month of November, the four weeks ended November 26, 2006, an increase of 9 percent from $4.45 billion in the same four-week period last year.

For the first thirteen weeks of its reporting period ended November 26, 2006, the Company reported net sales of $14.99 billion, an increase of 8 percent from $13.85 billion during the similar thirteen-week period of the prior year.

Comparable sales for the four-week and thirteen-week periods ended November 26, 2006, were as follows:


                            4 Weeks    13 Weeks
                            -------    --------
        US                     4%          3%
        International         10%         11%

        Total Company          5%          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 2328170). This recorded message will be available today through 5:00 p.m. (PT) on Friday, December 1, 2006.

The Company plans to release its operating results for the first quarter (12 weeks) of its fiscal year 2007 ended November 26, 2006, on December 14, 2006. A conference call to discuss these first quarter results is scheduled for 8:00 a.m. (PT) on December 14th and will be available via a webcast on www.costco.com (click on Investor Relations and "Webcasts").

Costco currently operates 503 warehouses, including 371 in the United States and Puerto Rico, 70 in Canada, 18 in the United Kingdom, five in Korea, four in Taiwan, five in Japan and 30 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 one additional new warehouse prior to the end of calendar year 2006 -- on Saturday, December 2nd, in Chester, England.

Certain statements contained in this document 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, 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 Bob Nelson, 425/313-8255 Jeff Elliott, 425/313-8264

Costco Wholesale Corporation Reports November Sales Results