iPhone 5S, 4.5G desteklemektedir. Ek olarak desteklenen frekanslar ve hızlar şu şekilde:

4G bantlarıLTE band 1(2100), 2(1900), 3(1800), 4(1700/2100), 5(850), 8(900), 13(700), 17(700), 19(800), 20(800), 25(1900) - A1533 GSM, A1533 CDMALTE band 1(2100), 2(1900), 3(1800), 4(1700/2100), 5(850), 8(900), 13(700), 17(700), 18(800), 19(800), 20(800), 25(1900), 26(850) - A1453LTE band 1(2100), 2(1900), 3(1800), 5(850), 7(2600), 8(900), 20(800) - A1457LTE band 1(2100), 2(1900), 3(1800), 5(850), 7(2600), 8(900), 20(800), 38(2600), 39(1900), 40(2300) - A1530HızHSPA 42.2/5.76 Mbps, LTE Cat3 100/50 Mbps, EV-DO Rev.A 3.1 Mbps