US Mobile frequency bands

Verizon, U.S Cellular, Sprint, and other CDMA Carriers : For example, Barring the iPhone 4 all Verizon and U.S Cellular iPhones are compatible with MetroPCS. That said, a majority of other phones that have been using Sprint, Verizon or US Cellular networks will not work with MetroPCS.

For 5G, T-Mobile is using band 71 (600 MHz) for low-band , band 41 (2,500 Mhz) for mid-band, as well as faster mmWave in select downtown areas. In 2013, they purchased MetroPCS and merged networks.

Yes, Metro uses T-Mobile’s GSM network . If you’re coming from T-Mobile or AT&T, which both run on GSM networks, your phone will likely be good to go as long as you unlock it and purchase a Metro SIM card. If you’re switching from Verizon, though, you may run into issues, since both of those carriers run on CDMA.

T-Mobile: 92% of MetroPCS CDMA subs moved onto GSM network amid shutdown in 3 markets | Fierce Wireless.