← Glossary · Calling, messaging & Wi-Fi
VoLTE
Voice over LTE — voice calls carried as data over the 4G network. Mandatory in the US since 3G shutdown in 2022. Older phones without VoLTE can't make calls on most US networks.
VoLTE (Voice over LTE) is the technology that carries voice calls as IP data over the 4G LTE network instead of the older circuit-switched 2G/3G voice channels.
Why it matters now
All US major carriers shut down their 3G networks in 2022 (Verizon, AT&T) and 2023 (T-Mobile). With 3G gone, VoLTE is the only way most phones make voice calls on US networks. If you bring a phone older than ~2014 or one not certified for VoLTE on your target carrier, it won't make calls — it might still text and use data, but voice calls fail.
Carrier VoLTE certification
Carriers maintain compatibility lists of phones certified to use VoLTE on their network. A phone might support VoLTE in general but not be on a specific carrier's list, especially if you're bringing an unlocked phone from outside the US. Run your phone's IMEI through your target carrier's "bring your own device" check page before switching.
VoLTE benefits
Aside from being mandatory, VoLTE gives you HD Voice quality (much better audio than legacy networks), faster call setup, and the ability to use voice and data simultaneously over the same connection (older networks made you choose).