The deal is worth $100 million yearly and involves the use of about 360 J.B. Hunt trucks and drivers and more than 1,000 trailers.
Hunt said Wal-Mart had been using 50 separate carriers for the tasks.
"We are pleased to be the sole transportation and logistics provider," said Paul Bergant, chief marketing officer for J.B. Hunt Transport.
Bentonville, AR-based Wal-Mart's vice president of corporate traffic, Ted Wade, said it would be simpler and cheaper to use a single source.
"That will help us lower transportation costs to benefit our customers," Wade said.