Originally Posted by
nkedel
If using regular wifi calling (on supported phones) just be careful that it IS actually in wifi calling mode, as otherwise it will get charged as a regular phone call. I've had a couple of charged calls because incoming calls came through via roaming when I thought wifi calling was on (luckily in 20c/minute countries.)
I've had that happen too.
There was another report here of someone calling a non-US number from a non-20¢/minute location and getting the full roaming charge, even though the call was a WiFi call.
Calling back to a US number over WiFi shouldn't be an issue.