Costco Wholesale Corporation reported net sales of $7.25 billion for the month of
July, the four weeks ended July 29, 2012, an increase of 8
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.

                                                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% ========= =========