How do I activate/setup Wi-Fi Calling? To activate Wi-Fi Calling visit one of these four major US carriers web sites: T-Mobile Sprint AT&T Verizon Created: Jan 11, 2017 - 4:16am Updated: Dec 11, 2020 - 4:31am Author: UIT Support Center Article: 2804 Was this article helpful? No Yes Thank you for your feedback. Click Here to submit again.