VoNR is VoLTE for 5G Standalone. Same IMS core. 5G NR air interface. EVS fullband codec. This is the complete UK technical reference for VoNR – how it works, where it is deployed, and what it means for phones, routers, and networks.
VoNR (Voice over New Radio) is the 3GPP-standardised mechanism for delivering voice calls over a 5G Standalone (5G SA) network using the IMS. It requires the 5G Core (5GC) rather than the 4G EPC, and supports the EVS codec for fullband audio. It is defined from 3GPP Release 15 onwards.
VoNR (Voice over New Radio) is the 5G evolution of VoLTE. Where VoLTE carries voice over 4G LTE using the EPC and IMS, VoNR carries voice over the 5G New Radio air interface using the 5G Core (5GC) and the same IMS. The signalling protocol is still SIP. The media still travels as RTP. But the radio layer, the core network, and the available codecs are all next-generation.
VoNR requires 5G Standalone (5G SA) deployment. Most current UK 5G is Non-Standalone (NSA), which uses the 4G EPC for control functions and therefore delivers voice via VoLTE, not VoNR. As UK operators build out 5G SA infrastructure, VoNR becomes the default voice mechanism for 5G-connected devices.
Technical reference for 5G voice – from the 3GPP specifications to UK operator timelines and device compatibility.
The 5GC architecture, NG-RAN, NR-IMS integration, QoS flows replacing LTE bearers, and how SIP call setup differs from VoLTE.
Enhanced Voice Services delivers super-wideband and fullband audio – 20 kHz capture vs AMR-WB’s 7 kHz. The biggest leap in voice quality since HD Voice.
VoNR only works on 5G Standalone. Most current UK 5G is NSA. This is the most important distinction to understand before planning VoNR deployment.
Where UK operators stand on 5G SA deployment and VoNR availability. EE, Vodafone, O2, and Three – current status and timelines.
Which handsets support VoNR, how to tell if a call is VoNR, and why most 5G phone users are still on VoLTE in 2025.
From 1G analogue to 5G VoNR – the complete evolution of mobile voice technology in the UK. Every generation, every codec, every transition.
To understand VoNR, you need to understand VoLTE. The IMS architecture, SIP signalling, QoS bearer design, ISIM provisioning – all of it carries over from VoLTE to VoNR. The 4G voice standard is the foundation.