iPhone 12 could have a big 5G problem — here’s why

iPhone 12 5G dual SIM
(Image credit: Apple)

These days it’s not uncommon to need more than one phone number, which is why many smartphones supports dual SIM. Even iPhones do, in their own special way, though it took Apple until 2018 to make it happen.

But fans of dual SIM and 5G may want to avoid the iPhone 12, because it sounds like you’re not allowed to have both running at the same time.

Unlike most phone makers who simply make room for two nano SIM cards inside their devices, Apple does not. Instead it offers a single slot for a nano SIM card and offers dual SIM support via the eSIM, which naturally restricts your extra number to a network that supports it.

Unfortunately, whichever one you prefer to use, it sounds like you’ll have to disable the second SIM slot if you want to use 5G. Or so says a screenshot posted on Reddit alleging to be from a training document from Apple’s Sales Web resources (via MacRumours), which details the answer to questions about whether 5G and dual SIM will work in tandem.

“When using two lines in Dual SIM mode, 5G data isn’t supported on either line and will fall back to 4G LTE. If customers are using eSIM only and are on a 5G-supported carrier and service plan, they’ll have 5G access.” 

Interestingly that last line implies 5G is only supported with the eSIM, rather than the nanoSIM. That doesn’t sound right, because even the small print on the iPhone 12 product page points out not all carriers support eSIM. We can’t find any evidence of Apple saying 5G is an eSIM exclusive on its support pages, so we’ll assume that it’s just a badly phrased answer unless we hear otherwise.

But in any case it sounds like dual SIM and 5G aren’t going to be compatible. Or at least not soon, since the Reddit user that posted the original screenshot of the training documents claims it’ll be fixed via an update later this year.

So hopefully it’ll just be a temporary blip, assuming it’s actually the case on October 23.

Tom Pritchard
UK Phones Editor

Tom is the Tom's Guide's UK Phones Editor, tackling the latest smartphone news and vocally expressing his opinions about upcoming features or changes. It's long way from his days as editor of Gizmodo UK, when pretty much everything was on the table. He’s usually found trying to squeeze another giant Lego set onto the shelf, draining very large cups of coffee, or complaining about how terrible his Smart TV is.

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