Millions of T-Mobile customers across the United States were left without reliable cell service Monday after a widespread network outage disrupted calls, text messaging and mobile data, leaving many smartphones displaying only “SOS” mode for several hours.
The outage began around 4 p.m. Eastern, with reports quickly pouring into outage tracking website Downdetector from customers who suddenly lost service. Within an hour, more than 62,000 outage reports had been submitted, making it one of the largest wireless disruptions reported this year.
Customers from states including California, Arizona, Georgia and Utah were among those reporting problems. Many said they were unable to place regular phone calls, send text messages or use cellular data, while others found their phones displaying “SOS” or “SOS Only,” indicating the devices could only connect to emergency services.
The disruption quickly became a trending topic on social media as frustrated customers tried to determine whether the issue was isolated to their devices or affecting the carrier nationwide. Some users attempted restarting their phones or toggling Airplane Mode without success while the outage was ongoing.
Several hours after reports first surfaced, T-Mobile acknowledged the issue in a public statement, saying its engineers were working to restore service as quickly as possible.
“Our teams are actively working the reports of technical challenges impacting some customers,” the company said. “Any service impacts are in the process of being resolved and are our highest priority. We know how critical it is to stay connected, and every available resource is focused on resolving this as quickly as possible.”
Although service gradually began returning for some customers Monday evening, others continued reporting intermittent issues as the network stabilized.
Later Monday night, T-Mobile announced that service had been fully restored nationwide.
“We have fully restored service for all customers and sincerely apologize for the difficulties,” the company said in a follow-up statement. “We know that customers rely on us to stay connected to what matters most, and we appreciate their understanding as we prioritized resolution.”
The wireless carrier has not disclosed what caused the outage. Company officials confirmed that engineers resolved the technical issue but did not say whether it stemmed from a software problem, equipment failure or another network issue.
Downdetector collects outage information through user-submitted reports, meaning the actual number of affected customers may have been significantly higher than the reported figures. The platform showed complaints steadily declining Monday evening as service returned across much of the country.
For many iPhone users, the appearance of “SOS” mode caused confusion. The status typically appears when a phone cannot connect to its carrier’s network but can still place emergency calls using another available cellular network. It does not necessarily indicate a problem with the phone itself and often disappears once normal carrier service resumes.
Customers who continued experiencing issues after T-Mobile announced the outage had ended were encouraged to restart their devices or briefly enable and disable Airplane Mode to force a fresh connection to the carrier’s network. Users on T-Mobile’s online support forums and Reddit also reported that rebooting their phones resolved lingering connectivity problems after service was restored.
While large-scale outages remain relatively uncommon among major U.S. wireless providers, they can have widespread consequences as millions of Americans rely on cellular networks for phone calls, text messaging, internet access, banking verification codes, navigation and emergency alerts.
