Costco Wholesale Corp., the nation’s largest chain of membership warehouses, on Wednesday posted growth in earnings, revenue and comparable-store sales for the first quarter, aided by increased traffic at its stores and website.

Comparable-store sales increased 5% from the same period a year ago, including 6% growth in the United States and 1% growth internationally.

ISSAQUAH, Wash. — Costco Wholesale Corp., the nation’s largest chain of membership warehouses, on Wednesday posted growth in earnings, revenue and comparable-store sales for the first quarter, aided by increased traffic at its stores and website.

Costco Wholesale Corp., the nation’s largest chain of membership warehouses, on Wednesday posted growth in earnings, revenue and comparable-store sales for the first quarter, aided by increased traffic at its stores and website.

For the 12 weeks to November 23, Costco’s earnings per share rose 16.7% to $496 million on a 7.4% increase in revenue to $26.3 billion.

Comparable-store sales increased 5% from the same period a year ago, including 6% growth in the United States and 1% growth internationally. Excluding the negative impacts of gasoline price deflation and foreign exchange, comparable-store sales increased 7%, both in the United States and internationally.

The company also noted that membership fees rose 6% to $582 million.

Costco’s operating profit increased 15.3% to $770 million in the quarter, and its operating margin expanded 20 basis points to 2.9%.

Costco reported last week that net sales in November were up 7% from a year earlier and that comparable-store traffic had increased by 5%.

Costco opened seven new warehouses during the quarter — five in the United States, one in Mexico and one in Australia. It now operates 671 warehouses, 474 of which are in the United States and Puerto Rico. It also has 88 warehouses in Canada, 34 in Mexico, 26 in the United Kingdom, 20 in Japan, 11 in South Korea, 10 in Taiwan, seven in Australia and one in Spain.
Costco announced during the quarter that it had entered the China market by opening a store on Tmall, a Chinese-language online marketplace operated by Alibaba Group.

Alibaba’s Tmall Global platform allows overseas brands and retailers to establish a presence on Tmall.com and other online marketplaces without having to have a physical presence in China.

Costco will use the platform to offer health and beauty aids, dietary supplements, baby care goods, household items and the retailer’s private label Kirkland Signature products to Chinese consumers.