As USA Today reported, the new trade-in program will run for nine days beginning June 21, with customers able to bring in a working iPhone 4 or 4S for a credit of up to $150. That credit will go toward the purchase of a 16GB iPhone 5 at the retailer's current price.
Taken in combination with an instant $50 rebate, customers can get Apple's newest handset for free on a two-year contract. The only costs customers are likely to incur are applicable sales taxes and carrier activation fees.
The retailer determines the worth of a phone based on its physical condition, and interested customers can check the potential value of their devices on Best Buy's website. If the trade-in phone is deemed to be worth more than $150, the store will make up the difference with a Best Buy gift card.
Customers will have to sign up for a two-year deal with Verizon, AT&T or Sprint. The trade-in credit is applicable only in physical Best Buy and Best Buy mobile stores, and not on the retailer's online portal.
Best Buy told USA Today that the iPhone trade-in promotion it held earlier in June led to the biggest day ever for its four-year-old trade-in program.