How can you force only WiFi calls and disable cellular service when outside US

[Android Central Question]

I spend a lot of time outside the US. I got Google Fi to avoid cellular phone charges due to phone calls using WiFi. But there seems to be no way to force calls onto WiFi. When I discussed with Google they told me the phone will always default to whatever will provide better phone quality. But WiFi is free and cellular racks up huge charges. Any ideas. I'm using a Moto G7.

 

[UnyteLux]

What Google told you is essentially correct. Switching to cellular when there is no Wifi is default Android behavior and AFAIK it cannot be overriden. I often find myself in the same situation as you. I revert to a rather more extreme option - I simply deactivate my SIM and get all my calls on Wifi via Viber with whom I have a virtual number - at present this is limited to US, Canadian or UK numbers. There are other services that offer similar deals. Call quality can be an issue at times but it is easier to live with that than to get an eye watering phone bill at the end of the month just because you happened to be travellingg.

 

[hallux]

Use Hangouts Dialer, it'll even work with your Fi number. That will use WiFi or cellular data rather than the voice service.

You may need to enable Hangouts integration for texting, which I have anyway so I can get my texts on whatever device is in my hands at the time.