T-Mobile's most loyal customers are about to see their bills increase - here's why

Kerry Wan/ZDNET

If you're a T-Mobile customer, your rates might be on the rise.

After announcing a price bump less than a year ago, the mobile carrier is doing it again -- and once again, it's affecting customers on older plans.

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According to an internal memo to T-Mobile employees obtained by CNET, some legacy plans (plans that aren't offered to new subscribers but are still available to existing subscribers) will see a $5 per-line increase starting April 2, 2025. Since these legacy plans are retired, it means those subscribers are among the company's most loyal and long-term. T-Mobile blamed the increase on "rising costs."

Legacy plans will see the increase

Legacy plans include offerings like Magenta, Magenta MAX, Magenta 55+, ONE, and Simple Choice, but it's not clear which of these will see the increase. The new rates will not impact current plans like Go5G Next, Go5G Plus, and Essentials.

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If this increase affects you, you'll receive a text from T-Mobile as soon as March 13. "For the first time in nearly a decade," the text reads, "we're making an update to the price of some of our older monthly service plans." If you don't get a notification today, your rates aren't going up.

There is some good news

Jon Freier, president of T-Mobile's consumer group, apparently wrote in the memo that no line that received an increase as part of last year's bump will see another increase this time. If you were affected by the $5 hike last May, you should be unscathed this time.

All existing plans should stay the same for now.

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T-Mobile says that if your plan falls under the "Un-contract Promise," which guarantees your rates won't increase, it will pay your final month's recurring service charge if you decide to leave (as long as you let the company know within 60 days).