@stujr@bsd.cafe

It depends on the carrier, sadly.

AweSIM (our MVNO) and T-Mobile work well (4G and VoLTE working). IIRC Verizon does not work at all (someone correct me if I'm wrong).

Have a look at
https://source.puri.sm/Librem5/community-wiki/-/wikis/Cellular-Providers