NEW YORK — Costco Wholesale Corp. and BJ’s Wholesale Club Inc. turned in healthy same-store sales gains in April.

Costco Wholesale Corp. and BJ’s Wholesale Club Inc. turned in healthy same-store sales gains in April.

Costco said Thursday that same-store sales in the United States, excluding gas inflation, rose 6% in April. That beating financial analysts’ forecast for a 4.3% increase.

The chain reported that inflation was affecting groceries as well, noting that food companies were passing on the increased cost of ingredients and shipping. Fresh food prices at the warehouse club operator rose by mid-to-high single digits, the company noted.

Internationally, Costco saw comparable-store sales surge 10%, excluding fuel business. That increase gave the retailer overall same-store growth of 7% for April.

Meanwhile, same-store volume at BJ’s climbed 8.5% in April, as shoppers purchased such staples as groceries. The gain was just short of analysts’ projection of 8.6%. Excluding gasoline, the same-store sales increase was 4.1%, BJ’s said Thursday.

BJ’s sales of consumables, particularly fresh food, advanced as customers turned to the warehouse club operator for cheaper groceries. This year’s later Easter also lifted revenue.

Still, softer demand for such categories as clothing, cigarettes, diapers, paper, soda and sporting goods pushed down sales of general merchandise by 1%.