Costco Wholesale Corporation reported net sales of $6.09 billion for the month of May, the four weeks ended May 30, 2010, an increase of 11% from $5.47 billion in the same four-week period last year.


In the U.S., this year's four-week period for May included 28 days of sales compared to 27 last year; the Memorial Day holiday fell in the reporting month of May last year but not this year. The holiday shift positively impacted this year's May total and comparable sales by approximately two percent (three percent in the U.S.).

For the thirty-nine weeks ended May 30, 2010, the company reported net sales of $57.17 billion, an increase of 10% from $52.15 billion during the similar period last year.


Comp stores sales grew 7% in the United States  and 17% internationally for a total comps rate of 9% during the four-week period. Excluding gas sales, comps growth clocked in at 5% domestically and 9% internationally for a total growth rate of 5%.