Verizon supports an “Advanced Calling” feature that supports a Wi-Fi Calling option when no cellular network service is available.
Note that there is no option to use Wi-Fi exclusively. If cellular service is available, the phone will use that. The ideal solution would be to have an additional feature:
- Wi-Fi Calling only – disable cellular service, enable Wi-Fi Calling.
Fortunately, there is a simple work-around that does this. For example, on an Android phone, do the following:
- Enable and configure the Advanced Calling feature, which includes Wi-Fi Calling
- Turn on Airplane Mode, which disables all of the phone’s RF Interfaces (Cellular, Wi-Fi, Bluetooth)
- Enable the Wi-Fi interface
- Connect to the Wi-Fi network.
To restore cellular voice service, simply turn off Airplane Mode.
Note: I found this solution via a Google search for “Verizon Wi-Fi Calling.”. It works on my three-year old Samsung Galaxy 5 currently running Android 6.0.1. There is no guarantee it will work on all Android phones.