“T‑Mobile will never change the price you pay for your T‑Mobile ONE plan.” That was the promise. The Un-contract. The whole reason millions of customers picked the magenta team over Verizon and AT&T in the first place. Now T-Mobile is retiring legacy 3G and 4G-era plans — Magenta, ONE, Simple Choice — and automatically moving customers onto “modern” 5G plans at higher monthly costs. Billing changes hit mid-July for the current wave. The company that swore it would never surprise you with a rate hike just sent the notification.
I was on tmo for 15 years. Switched to Mint and am paying less for both phone and home internet and its tmo’s network still. Unless you’re taking advantage of some of their odd benefits there no reason to stick with them.