U.S. gaming retailer GameStop is offering customers $50 credit when trading in selected Xbox 360 games for their Xbox One equivalents, the company has announced.

The promotion includes standard edition versions Call of Duty: Ghosts, Madden NFL 25, FIFA 14, Battlefield 4, and Assassin's Creed IV: Black Flag.

Customers must be a member of GameStop's PowerUp Rewards program, and purchase an eligible Xbox 360 game within 30 days of its launch. After purchasing the Xbox 360 game, the customer will receive a coupon in their PowerUp Rewards account that will allow the game to be traded in for $50 credit towards the Xbox One version. The coupon must be used before the end of 2013.

GameStop says the promotion will run across all of its U.S. stores.

"This offer gives [GameStop's PowerUp Rewards] members the chance to upgrade their current Xbox 360 game for the new Xbox One standard version of that game for $9.99," said GameStop senior vice president of merchandising Bob Purzon.

Microsoft yesterday revealed the final contents of the Xbox One retail package via an unboxing video, confirming that the machine would come with a mono headset and 4K HDMI cable. The retailer has previously said preorders of the Xbox One are "through the roof."

This article was updated on 08/09 to clarify the terms of the promotion.