ZDNET\u2019s key takeaways<\/h3>\n\n- Some iPhone 18 Pro Max users on AT&T are losing cellular service.<\/li>\n
- Apple said two updates can help prevent the issue.<\/li>\n
- Affected phones require a free hardware replacement.<\/li>\n<\/ul>\n
\nIf your iPhone 18 Pro Max<\/a> has lost service on AT&T and is unable to make calls, send texts, or even use mobile data, two new software updates won\u2019t be enough to get it working again. But Apple will replace the phone for free.<\/p>\nA couple of weeks ago, iPhone 18 Pro Max owners on AT&T began reporting they had lost cellular service. AT&T initially directed customers to install iOS 27.0.1 \u201cimmediately,\u201d warning the problem could prevent calls to 911.<\/p>\n
Also: iOS 27.0.1: Apple fixes annoying iPhone 18 Pro restart issues<\/a><\/strong><\/p>\nApple has now confirmed to ZDNET that an issue affecting \u201ca small number of iPhone 18 Pro Max users\u201d on AT&T\u2019s network may cause their devices to lose service. \u201cWe released iOS 27.0.1 earlier this week and strongly encourage all iPhone 18 Pro Max users to update now, and are also issuing a carrier settings update today,\u201d Apple said. \u201cThese updates together are meant to help prevent this issue from occurring.\u201d<\/p>\n
Since the updates are intended to prevent the issue, they won\u2019t fix devices already affected. Those will require a replacement, according to Apple.<\/p>\n
What\u2019s happening?<\/strong><\/h2>\niPhone 18 Pro Max owners on Reddit have reported randomly losing their connection<\/a> to AT&T, with phones switching to SOS mode<\/a>. While Wi-Fi still works, they can\u2019t make calls, send texts, or use data over the network.<\/p>\nAlso: 7 iOS 27 features that make old iPhones exciting again<\/a><\/strong><\/p>\nAT&T has subsequently sent a text to customers to warn them about an \u201cimportant Apple Software update\u201d that\u2019s available for affected phones. \u201cSome phones may be unable to complete calls\/text\/data, including to 911,\u201d the mobile carrier said. \u201cUpdate to iOS 27.0.1 immediately \u2014 Settings > General > Software Update.\u201d<\/p>\n
Apple has not provided an exact number of affected devices, though it has only observed the issue among iPhone 18 Pro Max users on AT&T.<\/p>\n
What\u2019s causing the AT&T issue?<\/strong><\/h2>\nApple and AT&T have not publicly explained the cause, but the iPhone 18 Pro Max\u2019s cellular hardware could be a factor. Our sibling site, CNET<\/a>, noted a recent iFixit teardown<\/a> shows the US version of the phone uses Qualcomm\u2019s Snapdragon X80 modem.<\/p>\nAlso: Your iPhone just got a hidden anti-scam upgrade in iOS 27<\/a><\/strong><\/p>\nHowever, CNET also cited a TechInsights teardown<\/a> that shows the iPhone 17 Pro and Pro Max<\/a> use the same modem, while the iPhone 18 Pro Max seems to add a new millimeter-wave antenna. Neither Apple nor AT&T has linked that antenna to the service failures.<\/p>\nFor now, the cause remains unconfirmed.<\/p>\n
What Apple and AT&T say to do<\/strong><\/h2>\nAccording to Apple, two new updates for iPhone 18 Pro Max users on AT&T are intended to help prevent the cellular connection problem, but they won\u2019t restore service to phones already affected.<\/p>\n
1. Install the iOS 27.0.1<\/strong> software update<\/h3>\nIf you have an iPhone 18 Pro Max on AT&T, Apple strongly recommends installing iOS 27.0.1. To check for the update, go to Settings > General > Software Update. AT&T is also urging customers to install the update.<\/p>\n
2. Install the carrier settings update<\/strong><\/h3>\nNext, install a new carrier settings update on your iPhone 18 Pro Max. It will automatically download for AT&T users over the next 14 days, according to Apple. To manually trigger it, go to Settings > General > About.<\/p>\n
What if you already lost service?<\/strong><\/h2>\nIf your iPhone 18 Pro Max is already without AT&T cellular service because of this issue, it cannot be reactivated through software updates and requires a hardware replacement instead, Apple said. The company confirmed to ZDNET that replacements will be provided free of charge.<\/p>\n
Also: 5 iOS 27 upgrades that make a big difference \u2013 and why I love them<\/a><\/strong><\/p>\nSo, affected owners can:<\/p>\n
\n- Contact Apple Support or AT&T.<\/li>\n
- Visit an Apple Store or an AT&T location.<\/li>\n<\/ul>\n
When contacting support, explain you have an iPhone 18 Pro Max on AT&T that has lost service, and mention whether you installed iOS 27.0.1 and the carrier settings update. From there, request your free replacement.<\/p>\n
AT&T previously told ZDNET that customers who continue to experience problems should seek additional support from Apple or an AT&T store. \u201cOur top priority is ensuring customers can stay connected when they need it most, and we are working with Apple to make it right,\u201d AT&T said.<\/p>\n
\n\n\n\n\n\t\t\t\t\t\t\n\t\t\t\t\t\t\t![\"Elyse](\"https:\/\/www.zdnet.com\/wp-content\/uploads\/sites\/3\/elyse-betters-picaro.jpg?w=64\")
\t\t\t\t\t\t<\/picture>\n\t\t\t\t\t<\/div>\n\n\n\t\t\t\t\t\t\tElyse Betters Picaro<\/span>\n\t\t\t\t\t\t<\/p>\n\t\t\t\t\t\t
\n\t\t\t\t\t\t\tEditor in Chief\t\t\t\t\t\t<\/span>\n\t\t\t\t\t<\/div>\n<\/p><\/div>\n\t\t\t\t\t\t\t\t
\n\t\t\t\t\t\t\t\t\t\t\tElyse Betters Picaro is editor in chief of ZDNET. Previously, she was EIC of Pocket-lint and operations manager at Valnet, overseeing its consumer tech brands such as XDA and Android Police.<\/span>
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\n\t\t\t\t\t\tSee full bio\t\t\t\t\t<\/a>
\n\t\t\t\t\t\t\t\t\t<\/span>\n\t\t\t<\/div>\n\t\t\t<\/p><\/div>\n
\n\n\n\n\t\t\t\t\t\t\n\t\t\t\t\t\t\t![\"Artie](\"https:\/\/www.zdnet.com\/wp-content\/uploads\/sites\/3\/artie.jpg?w=43\")
\t\t\t\t\t\t<\/picture>\n\t\t\t\t\t<\/div>\n
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If your iPhone 18 Pro Max<\/a> has lost service on AT&T and is unable to make calls, send texts, or even use mobile data, two new software updates won\u2019t be enough to get it working again. But Apple will replace the phone for free.<\/p>\n A couple of weeks ago, iPhone 18 Pro Max owners on AT&T began reporting they had lost cellular service. AT&T initially directed customers to install iOS 27.0.1 \u201cimmediately,\u201d warning the problem could prevent calls to 911.<\/p>\n Also: iOS 27.0.1: Apple fixes annoying iPhone 18 Pro restart issues<\/a><\/strong><\/p>\n Apple has now confirmed to ZDNET that an issue affecting \u201ca small number of iPhone 18 Pro Max users\u201d on AT&T\u2019s network may cause their devices to lose service. \u201cWe released iOS 27.0.1 earlier this week and strongly encourage all iPhone 18 Pro Max users to update now, and are also issuing a carrier settings update today,\u201d Apple said. \u201cThese updates together are meant to help prevent this issue from occurring.\u201d<\/p>\n Since the updates are intended to prevent the issue, they won\u2019t fix devices already affected. Those will require a replacement, according to Apple.<\/p>\n iPhone 18 Pro Max owners on Reddit have reported randomly losing their connection<\/a> to AT&T, with phones switching to SOS mode<\/a>. While Wi-Fi still works, they can\u2019t make calls, send texts, or use data over the network.<\/p>\n Also: 7 iOS 27 features that make old iPhones exciting again<\/a><\/strong><\/p>\n AT&T has subsequently sent a text to customers to warn them about an \u201cimportant Apple Software update\u201d that\u2019s available for affected phones. \u201cSome phones may be unable to complete calls\/text\/data, including to 911,\u201d the mobile carrier said. \u201cUpdate to iOS 27.0.1 immediately \u2014 Settings > General > Software Update.\u201d<\/p>\n Apple has not provided an exact number of affected devices, though it has only observed the issue among iPhone 18 Pro Max users on AT&T.<\/p>\n Apple and AT&T have not publicly explained the cause, but the iPhone 18 Pro Max\u2019s cellular hardware could be a factor. Our sibling site, CNET<\/a>, noted a recent iFixit teardown<\/a> shows the US version of the phone uses Qualcomm\u2019s Snapdragon X80 modem.<\/p>\n Also: Your iPhone just got a hidden anti-scam upgrade in iOS 27<\/a><\/strong><\/p>\n However, CNET also cited a TechInsights teardown<\/a> that shows the iPhone 17 Pro and Pro Max<\/a> use the same modem, while the iPhone 18 Pro Max seems to add a new millimeter-wave antenna. Neither Apple nor AT&T has linked that antenna to the service failures.<\/p>\n For now, the cause remains unconfirmed.<\/p>\n According to Apple, two new updates for iPhone 18 Pro Max users on AT&T are intended to help prevent the cellular connection problem, but they won\u2019t restore service to phones already affected.<\/p>\n If you have an iPhone 18 Pro Max on AT&T, Apple strongly recommends installing iOS 27.0.1. To check for the update, go to Settings > General > Software Update. AT&T is also urging customers to install the update.<\/p>\n Next, install a new carrier settings update on your iPhone 18 Pro Max. It will automatically download for AT&T users over the next 14 days, according to Apple. To manually trigger it, go to Settings > General > About.<\/p>\n If your iPhone 18 Pro Max is already without AT&T cellular service because of this issue, it cannot be reactivated through software updates and requires a hardware replacement instead, Apple said. The company confirmed to ZDNET that replacements will be provided free of charge.<\/p>\n Also: 5 iOS 27 upgrades that make a big difference \u2013 and why I love them<\/a><\/strong><\/p>\n So, affected owners can:<\/p>\n When contacting support, explain you have an iPhone 18 Pro Max on AT&T that has lost service, and mention whether you installed iOS 27.0.1 and the carrier settings update. From there, request your free replacement.<\/p>\n AT&T previously told ZDNET that customers who continue to experience problems should seek additional support from Apple or an AT&T store. \u201cOur top priority is ensuring customers can stay connected when they need it most, and we are working with Apple to make it right,\u201d AT&T said.<\/p>\n \n\t\t\t\t\t\t\tElyse Betters Picaro<\/span>\n\t\t\t\t\t\t<\/p>\n \t\t\t\t\t\t \t\t\t\t\t\t\t\t \t\t\t<\/p><\/div>\nWhat\u2019s happening?<\/strong><\/h2>\n
What\u2019s causing the AT&T issue?<\/strong><\/h2>\n
What Apple and AT&T say to do<\/strong><\/h2>\n
1. Install the iOS 27.0.1<\/strong> software update<\/h3>\n
2. Install the carrier settings update<\/strong><\/h3>\n
What if you already lost service?<\/strong><\/h2>\n
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\n\t\t\t\t\t\t\tEditor in Chief\t\t\t\t\t\t<\/span>\n\t\t\t\t\t<\/div>\n<\/p><\/div>\n
\n\t\t\t\t\t\t\t\t\t\t\tElyse Betters Picaro is editor in chief of ZDNET. Previously, she was EIC of Pocket-lint and operations manager at Valnet, overseeing its consumer tech brands such as XDA and Android Police.<\/span>
\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t
\n\t\t\t\t\t\tSee full bio\t\t\t\t\t<\/a>
\n\t\t\t\t\t\t\t\t\t<\/span>\n\t\t\t<\/div>\n\t\t\t\t\t\t<\/picture>\n\t\t\t\t\t<\/div>\n