NEW YORK WHOLESALE

ISSAQUAH, WA — Costco Wholesale Corporation ("Costco" or the "Company") (NASDAQ: COST) today reported net sales of $7.25 billion for the month of July, the four weeks ended July 29, 2012, an increase of eight percent from $6.74 billion during the similar period last year.

For the forty-eight weeks ended July 29, 2012, the Company reported net sales of $87.71 billion, an increase of nine percent from $80.18 billion during the similar period last year.

Comparable sales for these periods were as follows:

                                          4 Weeks    48 Weeks                                        ---------  ---------                 U.S.                        7%         7%                International               0%         6%                 Total Company               5%         7%                                        =========  =========  

Deflation in gasoline prices had a negative impact on comparable sales for the four-week period, while inflation in gasoline prices had a positive impact for the forty-eight week period; foreign currencies had a negative impact for both periods. Excluding these effects, comparable sales for these periods were as follows:

                                          4 Weeks    48 Weeks                                        ---------  ---------                 U.S.                        8%         6%                International               7%         9%                 Total Company               7%         6%                                        =========  =========  

Additional discussion of these sales results is available in a pre-recorded telephone message. You can access the recording by dialing 1-855-859-2056 (conference ID 28779893). This message will be available today through 5:00 p.m. (PT) on Friday, August 3, 2012.

Costco currently operates 605 warehouses, including 438 in the United States and Puerto Rico, 82 in Canada, 32 in Mexico, 22 in the United Kingdom, 13 in Japan, eight in Taiwan, seven in Korea and three in Australia. 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 up to an additional three new warehouses prior to the end of its fiscal year on September 2, 2012.

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 costs), energy, and certain commodities, 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.