T-Mobile said at CES that the company's unlimited plans will be the only option for new customers even though they are more expensive than some of its old, limited plans.

The company had said in August that it was phasing out its other plans in favor of unlimited. On Thursday, T-Mobile said those limited plans won't be sold anymore starting Jan. 22. Existing customers can keep their current plans.

T-Mobile today kicked off the next phase in its Un-carrier Movement. Speaking at the "Un-carrier Next" press event during CES in Las Vegas, T-Mobile president and CEO John Legere and COO Mike Sievert announced the Un-carrier is putting an end to all those monthly fees and added taxes, giving you the power to change the price you pay, and even putting money back in your pocket for data you don't use.

T-Mobile today went All In on T-Mobile ONE- wiping away monthly wireless service fees and even including all taxes on T-Mobile ONE. "When you sign up for T-Mobile ONE and AutoPay for $40 a line for a family of four, your bill at the end of the month is exactly $40 per line for your wireless service," T-Mobile said.

T-Mobile also unveiled KickBack on T-Mobile ONE. The company will now actually pay you back for what you don't use. When you use 2 GB or less in a month, you'll get an up to $10 credit on your next month's bill per qualifying line. So, you never have to guess how much data you'll use.

With an extra line costing just $20 on T-Mobile ONE (lines 3-12), you can add a line - for a tablet or family member - that could cost just $10 a month after KickBack.

T-Mobile also introduced the Un-contract for T-Mobile ONE - and announced a price guarantee on an unlimited 4G LTE plan. Now, T-Mobile ONE customers keep their price until they decide to change it. "T-Mobile will never change the price you pay for your T-Mobile ONE plan. When you sign up for T-Mobile ONE, only YOU have the power to change the price you pay," the company daid.

Legere also announced the Un-carrier is going 100% unlimited, and later this month, T-Mobile ONE will be the only postpaid consumer plan available from the Un-carrier - one subscription to the mobile Internet with unlimited everything. Existing T-Mobile customers can keep their current plans if they want.

However, T-Mobile's unlimited plan isn't exactly unlimited. If the network is busy, T-Mobile may slow speeds on customers that used more than 28 gigabytes.