Desperate for a new iPhone but have no money to spare? T-Mobile’s got you covered with an iPhone 6s plan that will only cost you $5 a month, or $9 for the larger 6s Plus, if you trade in your current phone.

T-Mobile’s Jump On Demand plan lets you upgrade your phone three times per year for a monthly hardware fee on top of your regular cell phone plan. The carrier had a similar promotion for the last-generation iPhones, but prices started at $15 a month. Sprint’s iPhone upgrade plan starts at $15.

If you don’t have a phone to trade in, you can still sign up for the Jump On Demand upgrade plan for $20 a month. Once the 18-month contract is up, you can pay off the phone for $125 less than retail. For a 16GB iPhone 6s, the total would come to $524.

Why this matters: Other carriers also offer inexpensive upgrade plans if you prefer to lease a phone rather than own it outright, but T-Mobile’s latest promotion is by far the cheapest. CEO John Legere said iPhone 6s preorders are up 30 percent over last year, which is in line with Apple’s estimates that this year’s launch weekend sales will beat last year’s. If you already preordered a phone, Legere said you can still take advantage of the Jump On Demand trade-in offer.

T-Mobile also confirmed that it will start selling Apple Watches on Friday. You can buy a watch online, but if you buy in-store, T-Mobile will sell you a Sport edition for no money down and no interest, with monthly payments of $14.54 for the 38mm model and $16.62 for the 42mm version. Those payments are spread over 24 months for “well-qualified customers” (in other words, you need good credit to finance a watch).

Sprint will also start selling Apple Watches on Friday, if you want to kill two birds with one stone.