So after 30 minutes on hold with Verizon Technical Support, I still have no conclusive answer to whether WiFi Calling works on a Verizon HTC One M9. They basically answered, "we don't know." I followed Verizon's Support pages and enabled HD Calling, but there's nothing in the interface to enable WiFi Calling.
Honestly, the very fact that I even need it, weak signal in the middle of Menlo Park, CA(!), which forces me to use an inadequate Samsung extender, where my calls go over my ISP is beyond belief. Why am I paying a premium to Verizon to ship the majority of my calls over the Internet anyway? Time to find another carrier.
If anyone can help, it'll keep me with Verizon, at least until I pay off the device.
I understand your desire to have WiFi calling on your M9 device, mbelanger-vzw. I can confirm that your device does not have the WiFi calling feature. Please see a complete list of devices that include the WiFi Calling feature on number 3 under Eligibility Requirements section at this link: http://spr.ly/658683zwk
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