Apple has officially confirmed that a subset of iPhone 18 Pro Max units used on the AT&T network in the United States is experiencing severe cellular connectivity failures. Affected devices may lose network access, rendering calls, texts, and data unusable, often leaving the phone stuck in SOS mode.
To prevent further issues, Apple released iOS 27.0.1 and a carrier settings update, version 72.1, on October 2. These updates are designed as a preventative measure for devices not yet showing symptoms. AT&T users are expected to receive the carrier update automatically within 14 days.
Apple clarified that these software updates cannot restore cellular functionality to devices that have already suffered a total service failure. For users whose phones are currently stuck in the SOS state, the company mandates a full device replacement through Apple Stores or AT&T retail locations.
The issue has been reported since the iPhone 18 Pro Max launch on September 18. While the problem is currently isolated to the US-specific model featuring the Qualcomm Snapdragon X80 modem paired with AT&T, Apple has not yet identified the root cause or confirmed if the hardware is at fault.
No official service program has been announced, but Apple advises affected users to contact customer support immediately for hardware replacement. The company maintains that this connectivity issue is limited to the specific combination of the US iPhone 18 Pro Max and the AT&T network.
