GoKawiilThere are many places where you can sell an unwanted phone, and trade-ins are the quickest and easiest way. Your options include chains like Best Buy or GameStop, as well as small-scale independent traders. Here you can sell your phone in exchange for store credit or, in cases such as GameStop or CeX, straight cash — though usually for less value when compared to the store credit. You can also trade-in at official stores like Apple or Samsung, either for an instant discount on a new device or for credit to use down the line.
This method offers a great many upsides over selling your phone yourself: you don't have to worry about anyone running off without paying (à la Facebook Marketplace) or whether your listing is seen in the first place, not to mention taking photographs and monitoring the account for purchase inquiries. On the other hand, you make much less money trading-in compared to selling yourself, as the cost of convenience comes out of the value you get back. Take the iPhone 17, for instance, which retails at $899 in the US. Apple's trade-in page asserts that the maximum value when returned (which assumes the phone is essentially good as new) will only be $585. Moreover, an Apple store will only pay you back in a discount or store credit. The same applies to Samsung, Best Buy, and many other retailers.