T-Mobile’s 4G LTE network uses bands 4/66 (AWS), 12, 2 (PCS), and 71 (600 mHz) . The 4G network acquired from Sprint uses bands 25, 26, and 41. 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.