Apple says iPhone 18 Pro Max AT&T faults need hardware replacement

Apple has confirmed an issue causing a small number of iPhone 18 Pro Max devices on AT&T to lose cellular service, and says affected devices will require a hardware replacement. Apple released iOS 27.0.1 earlier in the week and issued a carrier settings update, telling users to update now to help prevent the issue from affecting additional users on the AT&T network.zdnet.com+1

The confirmation matters because software alone cannot repair devices that have already dropped off the network. Apple said the updates are meant to prevent the issue from occurring, not to restore service on devices that have already lost it. That distinction separates users who can still update from users who need a physical replacement of the handset through Apple Support, an Apple Store, or AT&T.

What Apple confirmed

In a statement, Apple said: "We have identified an issue affecting a small number of iPhone 18 Pro Max users on the AT&T network that may cause a device to lose service and be unable to make calls." The company said it released iOS 27.0.1 earlier in the week and strongly encourages all iPhone 18 Pro Max users to update now.

Apple is also issuing a carrier settings update, which downloads automatically over the next 14 days. Users can trigger the download manually by opening Settings, choosing General, then About. The update for the iPhone 18 Pro Max moves the carrier settings version to 72.1, up from 72.0.2, and appears in the same About menu next to the carrier's name.

Apple released iOS 27.0.1 earlier in the week and said the software and carrier updates together are meant to help prevent the issue from occurring. Apple started requiring iPhone 18 Pro Max users to install iOS 27.0.1 in order to set up the device. The release notes for iOS 27.0.1 mention fixes for other bugs, including a Face ID issue affecting iPhone 18 Pro models.

How the updates work

AT&T sent a text message to customers that reads: "Action needed: An important Apple Software update for your iPhone 18 Pro Max is available. Some phones may be unable to complete calls/text/data, including to 911. Update to iOS 27.0.1 immediately." An AT&T spokesperson said customers should update to the latest available software.

Affected users see "SOS" in the iPhone status bar and cannot connect to AT&T's network for calls, texts, and data. Wi-Fi connectivity continues to work. The connectivity issues are not impacting every iPhone 18 Pro Max user on AT&T, and the problems only affect the iPhone 18 Pro Max, not other iPhone 18 models.

Who is affected and how

The U.S. version of the iPhone 18 Pro Max uses a Qualcomm modem, while the iPhone 18 Pro uses Apple's C2 modem and is unaffected by these AT&T connectivity issues. The iPhone 18 Pro Max in all other countries also uses Apple's C2 modem. It is unclear if the modem difference is a contributing factor.

AT&T said it is "working with Apple" on the issue and that customers who continue to experience problems can return to an Apple or AT&T store for additional support. Apple said affected users should contact Apple Support or AT&T, or visit an Apple Store or AT&T location to arrange a hardware replacement.

The underlying cause of the connectivity failure has not been disclosed by AT&T or Apple. A leaked AT&T email said iOS 27.0.1 is meant to help mitigate future impacts, though it is unclear if or how the update actually helps users who have already lost service on the network. Users who purchased or received the iPhone 18 Pro Max on the September 18 launch day had 2 October 2026 as the final day to return the device to Apple under the company's standard 14-day return policy in the U.S. Some customers said their request for a replacement under warranty was declined.

Apple has not said whether a follow-up update such as iOS 27.0.2 will be required as part of a fix, or whether the carrier update alone will be sufficient for users who have not yet lost service. Users who have already lost service should contact Apple Support or AT&T to arrange a hardware replacement.