I am not a professional smartphone tech. nor I.T. trained. You may wish to follow along with my own layperson thoughts that I am happy to share here after my research. Your own thinking & conclusions are also necessary. Hopefully I can save you some time by sending some of your thoughts in helpful directions & towards useful questions.

Choices; which WiFi Calling provider? More than one way to approach that question, as I now seem to have absorbed. We might have guessed: there can be numerous WiFi Calling plans with numerous phone service providers offered in one’s home country. There is a fairly quick way to narrow the choices down, as follows.

The pertinent question can be:  which providers offer WiFi Calling service:  1. for my particular brand of phone? &  2. my specific phone model? & 3. in my home country? It may be that specific, for finding compatible plans. The answer to those questions may identify one’s WiFi Calling provider choices, unless willing to change phones / buy a new phone. For me, the cost of buying another phone would likely outweigh the cost benefits of finding a best price WiFi Calling plan; e.g. if not traveling continuously.

With that approach, I engaged on a Chat Line on my phone brand’s website to ask for my WiFi Calling choices. For my specific phone model (we might even be asked for the phone’s IMEI number [the i.d. number assigned to that one phone] to get even more specific), I was advised of three phone service providers in my country (Canada) that offer WiFi Calling within some of their plans (with an unlocked phone one can consider changing providers). A next logical step if wishing to use my current smartphone for WiFi Calling could be to compare the WiFi Calling plan offerings of those three providers.

Many more WiFi Calling offerings to compare if willing to change phones. I started to see how many different options could be available in the USA. Let’s just say “Many”. One may need to include the cost of a new phone in the equation.

One can also explore installing a free WiFi Calling app on their smartphone. I am not clear yet if there may be some downside such as privacy issues when using these; that’s a question I haven’t looked into.