How to switch phone carriers without losing your number

Switching carriers is mostly waiting, and the parts that go wrong are the ones you were meant to collect first: an account number, a transfer PIN, an unlocked phone. One procedure per page, in the order it has to happen.

• US Cellular is now T-Mobile: what that means for roaming, international use and unlockingUS Cellular is now part of T-Mobile, and uscellular.com redirects there. Does US Cellular work abroad, charge for roaming, or unlock? What the pages say.
• When your phone unlocks: eleven carriers' rules, side by sideVerizon unlocks paid-off phones automatically. T-Mobile needs 40 days, Mint and US Mobile 60, Visible, Total and Cricket a year. Tello never locks. Sourced.
• Get these four things from your current carrier before you switchGet your account number, a transfer PIN, an unlocked phone and your device balance before you switch carriers. The checklist, in the order it matters.
• How to get a number transfer PIN from Verizon, AT&T, T-Mobile, Cricket, Xfinity and SpectrumWhere to get a number transfer PIN and how long it lasts: Verizon 7 days, Cricket 5, AT&T 4, Spectrum 72 hours, Xfinity reportedly 24. T-Mobile: lock off first.

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