GoKawiilReport details trade-offs of using Wi-Fi calling on smartphones
Wi-Fi calling quality depends heavily on network strength, with T-Mobile requiring at least 2 Mbps upload and download speeds and excluding satellite internet or hotspot connections. Switching between Wi-Fi and cellular mid-call relies on VoLTE support, and emergency calls are only routed over Wi-Fi when no cellular signal exists. A 2024 CISPA study found encryption vulnerabilities that exposed roughly 140 million Wi-Fi calling users before carriers patched the issues.