When it's time to upgrade to a new iPhone, Apple offers trade-in credits for eligible devices. But you're not limited to carrier promotions! Websites like Gazelle and marketplaces like Swappa allow you to trade in your device for cash or credit. Consider the pros and cons of each option: while carrier offers may require long-term agreements, trading with websites or marketplaces means sacrificing some profit potential. Regardless of which route you choose, be aware that your device's value will depreciate over time.

Source: https://www.cnet.com/tech/mobile/apple-iphone-16-trade-in-guide-how-to-use-your-old-phone-to-help-buy-a-new-one/#ftag=CAD590a51e