I'm going on 6 years. (In September.) I have never gotten a battery replacement. As I been reading people are urging me to get a new phone when the iPhone 13. (I've been talking to someone privately and they are urging me to go and get a new one when it becomes available. They are a member here, too.)My blind guess would be about 3 years before it gets serviced with a new battery or thrown into a landfill.