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Welp, turned off wi-fi calling but can't turn off VoLTE. I can set 3G, but since I'm on Fi, 3G won't work (T-mobile).. I get horrible 5G where I am, so it always goes to LTE.

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VoLTE will work over 5G (and sometimes over 3G in esoteric configurations). It is very data centric, even using SIP for call control. A rule of thumb is, any time you have a data connection, VoLTE can be used.

This is why Wi-Fi Calling and VoLTE took off at roughly the same time. Once you can route calls as data, you can offer it over both cellular and Wi-Fi. (Wi-Fi Calling has an additional outer IPsec layer, but it is the same "guts" inside the tunnel.)

> VoLTE will work over 5G

Doesn't 5G use VoNR? Or does VoNR imply the same SIP call format, but just over 5G instead of 4G?

My understanding is that VoLTE/VoNR/VoWiFi is all the same 3G era IMS stack (with updates since then) and thus SIP over IP over either GPRS Tunnel Protocol over low level radio interface or WiFi

That is my understanding of VoNR, but unfortunately I don't have experience with it.

If you are in the US, 3G is done from the big carriers. Verizon was the last hold out, only turning it off at the beginning of this year.

A shame! I have a Nokia Windows Phone that I used on 3.5G for a long time as a second phone, and now it's basically worthless other than maybe for a music player..

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