In a memo sent to employees, T-Mobile said it will be raising prices on some of its older plans, starting with the next bill. CNET reports: The memo was sent out by Jon Freier, president of T-Mobile's consumer group. The note doesn't list which plans are affected, but Freier specifically says that those on the carrier's latest assortment of Go5G plans will not see their prices increase. The same goes for the "millions of customers" who are covered by T-Mobile's Price Lock guarantee, which he says will continue to be in effect for those people. Freier says in the memo that T-Mobile is raising prices on older plans "for the first time in nearly a decade" and that the increases are designed to "keep up with rising inflation and costs." It isn't known exactly how many people will be affected by the change. The note says that it will affect a "small portion" of T-Mobile's customers. Those with free lines from the carrier will not see increases on those lines, T-Mobile confirmed to CNET. The company expects to notify all affected customers on Wednesday. T-Mobile previously tried to move customers on older, generally cheaper plans to some of its newer, pricier ones last year, only to back off the plan amid backlash. Whereas with that move people had the option to call T-Mobile's support and push back against the change, a source familiar with the company's plans tells CNET that this option won't be available with this new rate hike. Read more of this story at Slashdot.