iPhone 12 Models in Dual SIM Mode May Not Run at 5G Speeds, At Least Initially [Update: Confirmed]

Using an iPhone 12 in Dual SIM mode throttles the cellular data speed to 4G LTE, according to an Apple Sales FAQ shared with retailers and carriers.

Screen Shot 4
All 5G iPhone 12 models support Dual SIM mode, which refers to the ability to switch between a SIM card and an eSIM operating on independent numbers and/or carriers. However, an image of a training document from Apple's Sales Web resources called "What you need to know about 5G on iPhone" and posted to Reddit suggests the ‌iPhone 12‌ will not support 5G on either line when Dual SIM mode is active. The FAQ reads:

"Does 5G work with Dual SIM?"
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.

The document suggests that only by disabling one SIM or the other will 5G speeds be available – a limitation that, if confirmed, will come as a blow to ‌iPhone 12‌ customers who intended to use separate work and personal lines, for example.

5G dual sim incompatible
On the bright side, this incompatibility could be a software issue, and therefore something Apple could resolve down the line. Indeed, the Reddit user who posted the above image claims that an update coming later in 2020 will enable 5G when using a Dual SIM mode.

This information is allegedly revealed in Apple's internal training documents, but 5G is not anywhere mentioned in Apple's Dual SIM support page, which was last updated on September 26. We've reached out to Apple to clarify the matter and will update this article if we get a response.

(Thanks, De Paul Sunny!)

Update: MacRumors has received independent confirmation that the documentation is genuine.

Related Roundups: iPhone 12, iPhone 12 Pro
Tags: 5G, eSIM

Top Rated Comments

Jmausmuc Avatar
13 weeks ago


Here comes the “power users” that must have the already sparse 5G coverage at all times. ?

I personally use dual sim for international travel, it is a non-issue.

And of course... we will have many that claim it is a “deal breaker”

Good for you. I use dual sim 24/7 for work so the biggest feature of the iPhone 12 won’t work for me at all.
I have the right to be disappointed.
Score: 26 Votes (Like | Disagree)
Malus120 Avatar
13 weeks ago
That's pretty unacceptable if true, and if its unfixable is likely to be a deal breaker for a small but important minority of power users (myself included).

If this is anything more than just an initial software bug (AKA if this is a hardware limitation) I really have to question whether or not the iPhone 12 is ready for prime time.
Score: 19 Votes (Like | Disagree)
Jmausmuc Avatar
13 weeks ago
Are you kidding me?!

i will cancel my order of this is true.
Score: 17 Votes (Like | Disagree)
phatspider Avatar
13 weeks ago


Ok... show me show Sidney is blanketed in 5G... today

I assume you mean Sydney. Here is one of the 3 networks for this little village.
Covers where i live, work, run, drink, gym, BJJ and where 99% of my friends live.
Next?

Attachment Image
Score: 14 Votes (Like | Disagree)
Jmausmuc Avatar
13 weeks ago
Order is now cancelled, sticking with XS for another year. Disappointing because I was looking forward to some new tech, but since I don’t take many pictures, the iPhone 12 already felt like only a smalll update.

i would not be able to use 5G at all, because I use dual sim 24/7.

I am waiting for the next iPhone with hopefully real 5G (including international UW) support, 120hz and a smaller notch. That will feel much better
Score: 13 Votes (Like | Disagree)
phatspider Avatar
13 weeks ago


Ok.. show me the uk map of 5G...

Erm what again. Did you really think Sydney was in the UK? Cute.
There’s 193 other countries other than US and UK
Score: 13 Votes (Like | Disagree)

Top Stories

16inchmacbookpromain

Kuo: New MacBook Pro Models to Feature Flat-Edged Design, MagSafe, No Touch Bar and More Ports

Thursday January 14, 2021 9:32 pm PST by
Apple is working on two new MacBook Pro models that will feature significant design changes, well-respected Apple analyst Ming-Chi Kuo said today in a note to investors that was obtained by MacRumors. According to Kuo, Apple is developing two models in 14 and 16-inch size options. The new MacBook Pro machines will feature a flat-edged design, which Kuo describes as "similar to the iPhone 12" ...
iphone x camera close

iOS 14.4 Will Introduce Warning on iPhones With Non-Genuine Cameras

Thursday January 14, 2021 8:07 am PST by
In the second beta of iOS 14.4 seeded to developers and public testers this week, MacRumors contributor Steve Moser has discovered code indicating that Apple will be introducing a new warning on iPhones that have had their camera repaired or replaced with aftermarket components rather than genuine Apple components. "Unable to verify this iPhone has a genuine Apple camera," the message will...
prototype iphone 12 pro

Prototype iPhone 12 Pro Shown Off in Photos

Wednesday January 13, 2021 3:39 pm PST by
Developer Giulio Zompetti, who often shows off prototype versions of Apple devices, today highlighted a prototype version of the iPhone 12 Pro. The iPhone 12 Pro is running an operating system called SwitchBoard, a nonUI version of the iOS 14 update that Apple uses internally. We've seen SwitchBoard on prototype devices before, as Apple uses it to test new features. Zompetti's prototype...
foldable iPhone concept feature

Apple Testing In-Display Fingerprint Sensor for iPhone 13, Foldable iPhone Also in the Works

Friday January 15, 2021 1:46 pm PST by
Apple has started "early work" on an iPhone that has a foldable display, according to a new report from Bloomberg's Mark Gurman. Though testing of a foldable iPhone has begun, Apple has not committed to releasing a device that has a foldable display. Development has not yet expanded beyond a display and Apple does not have full foldable iPhone prototypes in its labs. Like foldable...
Apple TV Ray Light 2 Triad

Apple Extends Free Apple TV+ Trials Until July

Friday January 15, 2021 10:50 am PST by
Apple is once again planning to extend its free Apple TV+ trial subscriptions, this time until July. When Apple TV+ launched in November 2019, Apple offered free Apple TV+ subscriptions to those who purchased a new Apple device in or after September 2019. Those free subscriptions were set to expire in November 2020, but in October 2020, Apple announced that it was extending free trials...
macbook pro 16 inch thunderbolt

Bloomberg: Next-Generation MacBook Pro to Offer Improved Displays, Faster Charging Over MagSafe

Thursday January 14, 2021 11:36 pm PST by
Following today's report from analyst Ming-Chi Kuo outlining major changes for the next-generation MacBook Pro models coming in the third quarter of this year, Bloomberg's Mark Gurman has weighed in with his own report corroborating some of the details but seemingly differing a bit on others. First, Gurman shares more details on the return of MagSafe charging to the MacBook Pro, indicating...
Hue module dimmer switch

Philips Hue Announces New Wall Switch Module, Dimmer Switch, and Outdoor Light Bar

Thursday January 14, 2021 3:11 am PST by
Philips Hue has announced a new wireless dimmer switch module that lets Hue bridge owners directly control the smart lighting from their standard wall switches. The new Philips Hue wall switch module is the ideal addition to any Philips Hue set up. Installed behind existing light switches, it allows users to turn their existing switch into a smart switch and ensures their smart lighting is...
pat gelsinger intel

Incoming Intel CEO Derides Company's Inability to 'Deliver Better Products' Than Apple's M1 Chip

Friday January 15, 2021 6:17 am PST by
Incoming Intel CEO Pat Gelsinger has said that the company must "deliver better products" than Apple, which he described as a "lifestyle company," and says that Intel's best days are "in front of it" (via The Oregonian). Speaking at an Intel all-hands meeting yesterday, Gelsinger derisively implied that Apple is merely a "lifestyle company," so Intel must be able to surpass its technology: ...
mac pro mini feature

Apple Working on Two New Mac Pro Desktops, One of Which Will Be Reminiscent of Power Mac G4 Cube

Friday January 15, 2021 10:23 am PST by
Apple is developing two versions of the Mac Pro to succeed the Mac Pro that was first released in December 2019, according to a new report from Bloomberg. The first updated Mac Pro is a direct successor to the current Mac Pro and it will use the same design. It may also be equipped with Intel processors rather than Apple silicon chips, and it could be one of the sole machines in the Mac...
pioneer carplay wc5700nex

The Best Apple-Related Accessories at CES 2021

Wednesday January 13, 2021 1:16 pm PST by
CES 2021 is taking place digitally this year, and it hasn't been as exciting as in past years because many vendors have opted out. That said, some companies are still showing off some interesting Apple-related accessories that are coming out this year and that will be of interest to Mac, iPad, and iPhone users. Subscribe to the MacRumors YouTube channel for more videos. Pioneer Wireless...