Costco Wholesale Corporation reported net sales of $4.71 billion for the four-week retail reporting month of May, the four weeks ended May 28, 2006, an increase of 15% from $4.11 billion in the same four-week period of the prior fiscal year.

Net sales for the third quarter of fiscal 2006 increased 11% to $13.00 billion, from $11.75 billion during the third quarter of fiscal 2005. Net income for the third quarter of fiscal 2006 increased to $235.6 million, or $.49 per diluted share, from $209.8 million, or $.43 per diluted share, during the third quarter of fiscal 2005, representing a 14% increase in earnings per share.

Net sales for the first thirty-six weeks of fiscal 2006 increased 11% to $39.45 billion, from $35.50 billion during the first thirty-six weeks of fiscal 2005. Net income for the first thirty-six weeks of fiscal 2006 increased to $747.6 million, or $1.55 per diluted share, compared to net income for the first thirty-six weeks of fiscal 2005 of $708.4 million, or $1.45 per diluted share.

Net income for the first thirty-six weeks of fiscal 2005 was impacted by a one-time $52.1 million income tax benefit and a cumulative pre-tax, non-cash charge of $16.0 million ($10.0 million after-tax) concerning accounting for leases. Without these adjustments net income for the first thirty-six weeks of fiscal 2005 would have been $666.3 million or $1.36 per diluted share. Reported earnings per diluted share of $1.55 for the first thirty-six weeks of fiscal 2006 represents a 14% increase over this amount.

Comparable sales for the fiscal third quarter (twelve weeks) and first thirty-six weeks of fiscal 2006, both ended May 7, 2006, were as follows:

12 Weeks    36 Weeks
                          --------    --------
          US                 7%          7%
          International      8%          9%

          Total Company      7%          8%
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May Sales Results

The Company today also reported net sales of $4.71 billion for the four-week retail reporting month of May, the four weeks ended May 28, 2006, an increase of 15% from $4.11 billion in the same four-week period of the prior fiscal year. For the first thirty-nine weeks of its 2006 fiscal year ended May 28, 2006, which include the first three weeks of its fiscal fourth quarter, the Company reported net sales of $43.01 billion, an increase of 12% from $38.54 billion during the comparable period of the prior fiscal year.

Comparable sales for the four-week retail-reporting month of May and the 39-week retail-reporting period of September through May are as follows:

4 Weeks    39 Weeks
                          --------    --------
          US                 9%          8%
          International     17%         10%

          Total Company     10%          8%
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