Walmart Sam's Club closures spell gains for Costco: JP Morgan

A customer unloads a cart at a cash register at a Costco Wholesale store in Naperville, Illinois.
Daniel Acker | Bloomberg | Getty Images

Costco's recent success won't stall anytime soon with Walmart closing more Sam's Club stores, according to J.P. Morgan.

The wholesaler has the potential to open 15 stores per year for the next four years in the U.S., with international opportunities abound, wrote analyst Christopher Horvers on Friday.