Walmart is adding FedEx Office locations to about one-tenth of its U.S. stores. (FedEx)

Walmart is continuing to build on its efforts to become a one-stop shop in the Internet age. The retailer on Tuesday said it is adding FedEx Office locations, where customers can ship packages, drop off returns and pick up deliveries, to 500 of its U.S. stores.

The announcement follows a pilot program in which the companies tested FedEx stores in 46 Walmart locations in six years. Under the new program, FedEx Office will expand to about 10 percent of Walmart’s U.S. stores over the next two years.

The partnership “builds on a shared goal of providing customers convenience and value, so they can save both time and money,” Brian Philips, chief executive of FedEx Office, said in a statement.

In early tests, the companies found that many customers shopped at Walmart after visiting the FedEx store, Phillips told CNBC on Tuesday.

Walmart, based in Bentonville, Ark., has long been known for its sprawling supercenters, some of which include vision centers, pharmacies, nail salons, dry cleaners, bank branches, even eateries such as McDonald’s. The addition of FedEx, though, comes as the retailer invests heavily in its online business. Amazon.com, Walmart’s largest rival, now accepts returns at Kohl’s department stores and allows customers to pick up packages at a number of neighborhood stores and lockers. (Jeffrey P. Bezos, the founder and chief executive of Amazon, also owns The Washington Post.)

“Offering shipping services makes Walmart stores more relevant to the way customers live and work today,” said Craig Johnson, president of Customer Growth Partners, a retail research and consulting firm. “Customers want convenience, whether they’re shopping online or in the store.”

The announcement is the latest in a series of partnerships Walmart has unveiled in the past week, as the world’s largest retailer looks to build its online and delivery businesses. Handy, an installation and assembly service, will soon be available at nearly half of Walmart’s U.S. stores. (Amazon and Ikea also offer similar services.) And last week, Walmart announced that it would partner with ride-hailing service Uber to deliver groceries in 100 cities nationwide.

“Our busy customers view our stores as a one-stop-shop for all the products and services they are looking for,” Daniel Eckert, a senior vice president at Walmart, said in a statement.

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