ISSAQUAH, Wash. ( TheStreet) -- Costco ( COST), the warehouse retailer, said fiscal second-quarter earnings rose 25% as comparable-store sales increased 9%. Costco said it earned $299 million, or 67 cents a share, in the second quarter, up from $239 million, or 55 cents a share, a year earlier. The latest second quarter included a charge of 3 cents a share related to a change in employee benefits. Analysts surveyed by Thomson Reuters expected Costco to earn 72 cents a share in the second quarter. Second-quarter net sales rose 11% to $18.36 billion. U.S. same-store sales in the period rose 5%, or 2% excluding gas inflation and foreign exchange. International same-store sales soared 26%, or 10% excluding gas and forex. Costco also said same-store sales in February gained 9%, while net sales rose 11% to $5.61 billion. -- Reported by Joseph Woelfel in New York. Follow TheStreet.com on Twitter and become a fan on Facebook.