Through Sunday, Best Buy is guaranteeing those with a working iPhone 5 will get at least $200 in trade-in credit, while iPhone 4s owners will get $150 and iPhone 4 owners will get $100. Devices have to power on and be free of screen cracks and water damage.
The deals, combined with a $100 price drop on the iPhone 5s for Sprint and Verizon, mean that those signing up for a new contract on those carriers could actually get more for their old device than they need to pay for the new one. The AT&T iPhone 5s remains at the standard $199 price.
Earlier this spring, Best Buy offered a weekend of guaranteed $150 trade-ins for the iPhone 5 and iPhone 4s. Other big retailers have also banked on the high resale value of used iPhones to offer similar trade-in offers.