https://www.theverge.com/circuitbreaker/2018/3/2/17071404/sprint-iphone-x-lease-50-percent-off

If you’re willing to switch to Sprint (or add a new line) to save on the iPhone X’s regular $1,000 asking price, the carrier is running a somewhat decent deal right now. People who sign up for the company’s Sprint Flex 18-month lease program will pay $20 per month for the base model iPhone X. Usually that recurring payment is $41.67.

Sprint claims this to be “the lowest price” among carriers, but that’s slightly deceptive. When Sprint says lease, it really means lease. At the end of that 18-month term, you still don’t own the iPhone; you’ll have to decide whether to trade it back in for an upgrade or pay what’s left on the balance and keep it. Other carriers do monthly installments that end with you having paid the full price of the phone. After that, it’s yours. (Most of them have early trade-in programs and the like.)