An AT&T Outage Is Wreaking Havoc on US Cellular Networks

Started around 3:30 a.m. on the east coast, reports of flooding in about a AT&T cutting service. Customers complained on Reddit and X and logged their problems on Downdetector, a site that, well, detects when services fail.

The impact was widespread; AT&T users from New York to Atlanta to Dallas claimed they had no signal and phones were locked in SOS mode. Multiple police departments, including in San Francisco, reported that some users were unable to contact 911 as a result of the outages. As of 9 a.m. ET, Downdetector was showing more than 72,000 AT&T outages across the United States; The site’s baseline for AT&T service issues is 42.

“Some of our customers are experiencing wireless service outages this morning,” AT&T spokesman Jim Greer said in a statement. “We are working urgently to restore service. We encourage the use of Wi-Fi calling until service is restored.”

However, it’s not just AT&T customers. All cell phone carriers on Downdetector showed spikes Thursday morning, including giants Verizon and T-Mobile. But both companies confirmed that there is no problem with their networks; the complaints are more like collateral damage, people trying to reach their AT&T contacts and not getting through.

“We did not experience any outages,” a T-Mobile spokesperson told WIRED via email. “Our network is operating normally. “Downdetector likely reflects the challenges our customers had when trying to connect with users on other networks.”

Similarly, a Verizon spokesperson said via email that “the Verizon network is operating normally. “Some customers experienced issues this morning when calling or texting customers served by another provider.”

The news is not all bad. AT&T confirmed that FirstNet, the first responder network that AT&T built, is operating normally. And while it’s an imperfect substitute—or entirely unusable, depending on where you are—Wi-Fi calling should suffice as a workaround for now. (To activate Wi-Fi calling, go to your smartphone page Settingsso Network and internetthen change the Wi-Fi Calling Activate. The exact wording may vary depending on your phone model and operating system.)

Cellular network interruptions occur with some frequency and can be due to various causes. “Three things come to mind with major network outages,” says Erik Keith, senior research analyst at S&P Global Market Intelligence: “cyber attacks, fiber outages at critical points in the network, and software or system updates that They don’t go as planned.” or have unforeseen problems.”

In this case, the latter explanation seems the most likely, says Doug Madory, director of Internet analytics at Kentik, a network monitoring company. “It’s pretty unusual,” Madory says, noting that even within the same household some AT&T devices are affected while others are not. “My guess is that they did some kind of internal software and it disagreed with some subset of these devices, and they’re having trouble reversing it.”

While outages of this scale are rare, they occur globally once or twice a year. Last month, the Spanish airline Orange España lost half your network for hours due to a cyber attack. T-Mobile had a massive service outage of this scale a year ago that finally attributed to a “third-party fiber interruption problem.” However, that problem seemed more autonomous than the domino effects apparently caused by AT&T’s problems.