You could save serious money on the iPhone X if you buy it through Apple's upgrade plan (APPL)

iPhone X

Apple's just-announced iPhone X is its most expensive phone ever, with a max price of $1,149.

But paying the full price up front isn't the only way to buy the iPhone X when preorders start on October 27. There's also Apple's upgrade program, which allows you to pay off the device in monthly installments through a zero-interest loan.

And if you plan on upgrading to a new iPhone every year, Apple's plan could save you serious money.

Apple broke down on its website how much its three new phones — the iPhone 8, 8 Plus, and X — would cost in monthly payments:

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The base 64 GB iPhone X costs $49.91 a month. Since the plan allows you to swap in the phone for a new one after 12 payments, you'd have to pay only $598 before upgrading. The same iPhone X costs $999 to buy outright, so you'd essentially save $401 by paying through Apple's monthly program.

You save even more with the more expensive 256 GB iPhone X. One year's worth of payments at $56.16 a month equals $673.92, or a $475.08 savings off the full $1,149.

Since you don't get to keep the iPhone if you upgrade, Apple is basically giving you either a $401 or a $475.08 discount off the up-front price to take the iPhone back from you after one year. If you don't want to pay the full cost of the iPhone up-front and intend to upgrade every year, that's a good deal.

Experts already consider Apple to have the best monthly-payment program for buying iPhones. The company's AppleCare warranty, which covers accidental-damage repairs at a heavily reduced cost, is included with the program (a $200 value).

If you don't want to buy a new iPhone 8 or X through monthly payments, here's the full cost breakdown: