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
Related Forum: iPhone

Top Rated Comments

Jmausmuc Avatar
9 months 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
9 months 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
9 months ago
Are you kidding me?!

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

16 inch macbook pro m2 render

When Can We Expect the Redesigned MacBook Pros Now?

Wednesday June 16, 2021 7:11 am PDT by
With no sign of redesigned MacBook Pro models at this year's WWDC, when can customers expect the much-anticipated new models to launch? A number of reports, including investor notes from Morgan Stanley and Wedbush analysts, claimed that new MacBook Pro models would be coming during this year's WWDC. This did not happen, much to the disappointment of MacBook Pro fans, who have been...
2021 back t0 school

Apple Launches 2021 Back to School Promotion: Free AirPods With Eligible Mac or iPad Purchase

Thursday June 17, 2021 4:56 am PDT by
Apple today launched its seasonal back-to-school sale for the upcoming school year in the United States and Canada, offering students free AirPods alongside purchases of select Macs and iPad models. Similar to last year's promotion, this year's offer includes free AirPods alongside the purchase of a MacBook Air, MacBook Pro, the new 24-inch iMac, the Mac Pro, Mac mini, and the new M1-powered ...
maxresdefault

Apple CEO Tim Cook: Sideloading Apps Would 'Destroy the Security' of the iPhone

Wednesday June 16, 2021 10:49 am PDT by
Apple CEO Tim Cook this morning participated in a virtual interview at the VivaTech conference, which is described as Europe's biggest startup and tech event. Cook was interviewed by Guillaume Lacroix, CEO and founder of Brut, a media company that creates short-form video content. Much of the discussion centered on privacy, as it often does in interviews that Cook participates in. He...
YouTube Picture in Picture Feature

YouTube Says iOS Picture-in-Picture Coming to All US Users

Friday June 18, 2021 9:41 am PDT by
After a long wait, YouTube for iOS is officially gaining picture-in-picture support, allowing all users, non-premium and premium subscribers, to close the YouTube app and continue watching their video in a small pop-up window. In a statement to MacRumors, YouTube says that picture-in-picture is currently rolling out to all premium subscribers on iOS and that a larger rollout to all US iOS...
applecare lower prices

Apple Lowers Prices of AppleCare+ Plans for M1 MacBook Air and MacBook Pro

Thursday June 17, 2021 7:33 am PDT by
Apple today lowered the prices of AppleCare+ plans for MacBook Air and 13-inch MacBook Pro models equipped with the M1 chip. Coverage offered by the plans, as well as accidental damage fees, appear to remain unchanged. In the United States, AppleCare+ for the MacBook Air now costs $199, down from $249. The new price applies to both M1 and Intel-based MacBook Air models, although Apple no...
m1 v intel thumb

Intel Processor Market Share May Fall to New Low Next Year Due to Apple Silicon

Friday June 18, 2021 2:06 am PDT by
Intel may see its market share fall to a new low next year, in large part thanks to Apple's decision to move away from using Intel processors in its Mac computers and instead use Apple silicon. Apple announced last year that it would embark on a two-year-long journey to transition all of its Mac computers, both desktops, and laptops, to use its own in-house processors. Apple is expected to...
apple watch edition series 5 ceramic black prototype

Apple Planned Black Ceramic Apple Watch Edition Series 5

Wednesday June 16, 2021 5:45 am PDT by
Apple considered offering a black version of the ceramic Apple Watch Edition Series 5, according to newly-shared images of the prototype casing. The images, shared on Twitter by the prototype collector and leaker known as "Mr. White," show a prototype black ceramic Apple Watch casing, alongside the white ceramic version. The ceramic Apple Watch Edition Series 5 was never available in a...
maxresdefault

Demo: Check Out AirPlay 2 on a Mac in macOS Monterey

Tuesday June 15, 2021 11:57 am PDT by
With macOS Monterey, Apple has introduced expanded AirPlay 2 support, so you can AirPlay content from an iPhone, iPad, or even another Mac to your main Mac. We thought we'd do a quick demo of this handy new feature in our latest YouTube video. Subscribe to the MacRumors YouTube channel for more videos. With AirPlay to Mac, you can extend or mirror an Apple device's display to a Mac, and since ...
app store blue banner

U.S. Antitrust Legislation Would Require Users to Be Able to Delete All Pre-Installed Apple Apps [Updated]

Wednesday June 16, 2021 11:26 am PDT by
Update: Bloomberg inaccurately interpreted the original comments and has since drastically changed the wording of its article. The original Bloomberg piece said that Apple would be prohibited from pre-installing its own apps on iPhones. The updated Bloomberg article has been rewritten to clarify that the antitrust legislation prohibits Apple from preventing users from removing Apple-created...
3nm apple silicon feature

Apple Supplier TSMC Readies 3nm Chip Production for Second Half of 2022

Friday June 18, 2021 6:59 am PDT by
Apple supplier TSMC is preparing to produce 3nm chips in the second half of 2022, and in the coming months, the supplier will begin production of 4nm chips, according to a new report from DigiTimes. Apple had previously booked the initial capacity of TSMC's 4nm chip production for future Macs and more recently ordered TSMC to begin production of the A15 chip for the upcoming iPhone 13,...