In a text message sent to customers today, AT&T acknowledged that some iPhone 18 Pro Max devices on its network are experiencing cellular issues. AT&T said customers should immediately update to iOS 27.0.1, even though many affected users have said the update does not resolve the issues. There are now at least thousands of users who have experienced this issue, according to discussion topics on Apple Support Community Forums, Reddit, and MacRumors. Here’s what the text message says: Hello, this is AT&T. Action Required: An important software update is available from Apple for your iPhone 18 Pro Max. Some phones may not be able to complete calls, text messages, or data, including 911. Update to iOS 27.0.1 immediately: Settings > General > Software Update. Contact AT&T or Apple if you have questions. Apple’s release notes for iOS 27.0.1 did not mention a fix for AT&T’s cellular issues. Rather, the update fixed a Face ID issue on iPhone 18 Pro models. As we reported last week, affected iPhone 18 Pro Max users are unable to connect to the AT&T network for phone calls, text messages, or data persistently or intermittently and, as a result, their devices typically enter SOS mode. The underlying cause has not been confirmed and Apple has yet to publicly comment on the matter. Notably, the US version of the iPhone 18 Pro Max is the only new iPhone introduced last month that is equipped with a Qualcomm cellular modem. The smaller iPhone 18 Pro and iPhone Duo are equipped with Apple’s C2 modem worldwide, as is the iPhone 18 Pro Max in all other countries. However, it is unclear if this is a contributing factor. If a software issue is identified, another update, such as iOS 27.0.2, may be required. However, if there is a hardware problem, it would obviously be a much bigger problem. We will provide further updates as new information becomes available. (PS: There is some irony in AT&T sending a text message to warn iPhone 18 Pro Max users that they may not be able to send or receive text messages.)
