Cell Service Outage map websites

verizon

https://www.verizon.com/support/check-network-status/

ATT or DirecTV (you may have to log in)

https://www.att.com/outages/

T-Mobile

https://www.t-mobile.com/coverage/coverage-map

A website that attempts to generally detect both internet and cell outages

https://downdetector.com/

I just got an email from AT&T this morning, apologizing for the outage.
It also said I'll receive a credit for that, though it didn't give an amount.
I don't expect anything significant, but since I don't live on my phone, I don't recall having a problem.

The credit was announced today. Wait for it: $5.

I wasn't expecting much; good thing, huh ?