Apple Confirms Defect in Some 'iPhone 18 Pro Max' Phones in the US Requiring Replacement

Apple has confirmed a cellular connectivity issue affecting a small number of iPhone 18 Pro Max devices on the AT&T network in the United States, clarifying that devices that have already lost service cannot be restored via a software update and require replacement.

In a statement to 9to5Mac, Apple said it identified a problem that may cause some iPhone 18 Pro Max devices on the AT&T network to lose service and be unable to make calls.

The company’s confirmation follows complaints from users since the phone’s launch, who reported losing connection to the AT&T network and seeing the emergency SOS mode appear, preventing them from making calls, sending text messages, or using mobile data.

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Apple explained that it released iOS 27.0.1 and began rolling out a separate carrier settings update for AT&T, aimed at preventing the issue from affecting additional devices, urging iPhone 18 Pro Max users to install the latest available update.

However, the company emphasized that the updates will not restore service to devices that have already lost connectivity, and that these devices need to be replaced, urging affected users to contact Apple or AT&T support, or visit one of their stores.

AT&T had previously urged iPhone 18 Pro Max users to install iOS 27.0.1 immediately, warning that the issue could prevent making calls, sending text messages, and using data, including connecting to the emergency 911 service.

The U.S. version of the iPhone 18 Pro Max uses a Qualcomm modem, while versions sold outside the United States use Apple’s C2 modem. The iPhone 18 Pro also uses an Apple modem.

Apple has not yet disclosed the root cause of the issue, and there is no evidence to suggest that the Qualcomm modem is responsible.