Generally, VoLTE-supported handsets will show a VoLTE icon at the top of the screen near the signal bar to indicate that it is enabled. Once you see the VoLTE indicator displayed near the signal bar, go to the dial pad and dial the number which you want to reach.
- Xiaomi – dial *#*#86583#*#* to disable the carrier check setting and enable VoLTE.
- iPhone – all iPhones from iPhone 7 and above are VoLTE-supported, although this feature is turned off by default. To enable VoLTE on your iPhone, go to Settings > Mobile Data > Mobile Data Options > Voice & Data > enable VoLTE.