Costco April Comps Increase 10%

Costco Wholesale Corporation reported net sales of $3.56 billion for the four weeks ended May 2, 2004, an increase of 13 percent from $3.14 billion in the same four-week period of the prior fiscal year.

For the first 35 weeks of its 2004 fiscal year ended May 2, 2004, the Company reported net sales of $31.35 billion, an increase of 14 percent from $27.47 billion during the similar 35-week period of the prior fiscal year.

Comparable sales for the 4-week and 35-week periods ended May 2, 2004, were as follows:

                       4 Weeks        35 Weeks
                     ------------   ------------
US                            10%            10%
International                  8%            19%

Total Company                 10%            11%
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