WASHINGTON — AT&T said Thursday that all of its customers impacted by a nationwide service outage have cell service again, after an hourslong outage that appeared to be the result of a technical error, not a malicious attack.
An AT&T spokesperson said all service had been restored in an update shortly before 3:30 p.m. Eastern, nearly 12 hours after customers began reporting issues.
“We have restored wireless service to all our affected customers," AT&T said. "We sincerely apologize to them. Keeping our customers connected remains our top priority, and we are taking steps to ensure our customers do not experience this again in the future.”
AT&T blamed the incident on an error in coding, without elaborating.
“Based on our initial review, we believe that today’s outage was caused by the application and execution of an incorrect process used as we were expanding our network, not a cyber attack,” the Dallas-based company said.
Downdetector, which tracks online outage reports submitted by users, showed more than 74,000 AT&T customers reported issues at the peak of the outage. By noon Eastern, that number had declined to about 60,000 reported outages.
The outages began around 3:30 a.m. ET. The carrier has more than 240 million subscribers, the country's largest.
So far, no reason has been given for the outages. But Lee McKnight, an associate professor in the iSchool at Syracuse University, believes the most likely cause of the outage is a cloud misconfiguration, or human error.
"A possible but far less likely outcome is an intentional malicious hack of ATT’s network, but the diffuse pattern of outages across the country suggests something more fundamental,” McKnight said in an emailed statement.
While the outage tracking website also showed 4,000 outage reports for Verizon and more than 1,900 from T-Mobile, both companies said in their statements they didn't experience outages.
“Verizon’s network is operating normally. Some customers experienced issues this morning when calling or texting with customers served by another carrier. We are continuing to monitor the situation,” Verizon said.
“Our network is operating normally. Down Detector is likely reflecting challenges our customers were having attempting to connect to users on other networks,” T-Mobile said.
Cricket Wireless, which is owned by AT&T, had more than 9,000 outages, Downdetector said Thursday.
During the outage, customers still had access to "SOS mode," which allows cell phone users without access to regular service to call 911 in an emergency, piggybacking off of other networks nearby to do so.
The outage became a major trend on social media overnight, with users on X (formerly Twitter) flocking to a number of hashtags to discuss the issue. Although #CyberAttack was one of the trending hashtags associated with the outage, there is no indication that an attack was the cause of the outage.
The Associated Press contributed to this report.