It’s The End for 3G service To make room on Towers for 5G 

AT&T will shut down its 3G network Today

3G phones Will Not work on 5G

If you own a 3G phone or a phone that doesn’t support HD Voice calls, then it will no longer make or receive calls or text messages, And those devices can’t dial 911.

other devices that are affected by the end of 3G service

are e-book readers, vehicle SOS services like On Star, home alarms, medical alert devices and more.

When will T-Mobile end 3G? What are the Verizon 3G plans?

T-Mobile says it will retire the old  Sprint network on March 31.  It will shut down its own on July 1.

Verizon said it plans on Dec. 31, 2022.