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
25 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
25 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
25 weeks ago
Are you kidding me?!

i will cancel my order of this is true.
Score: 17 Votes (Like | Disagree)
phatspider Avatar
25 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
25 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
25 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

samsung experience 1

Samsung's 'iTest' Lets You Try a Galaxy Device on Your iPhone

Thursday April 8, 2021 12:42 pm PDT by
Samsung has launched "iTest," an interactive website experience that's designed to allow iPhone users to test out Android on a Galaxy device, or "sample the other side," as Samsung puts it. Subscribe to the MacRumors YouTube channel for more videos. The iTest website is being advertised in New Zealand, according to a MacRumors reader who came across the feature. Visiting the iTest website on...
sonny 2021 ipad mini pro dummies

Leaked Dummy Units Show iPad Mini 6 With Thick Bezels and Home Button, New iPad Pro Models

Thursday April 8, 2021 2:11 am PDT by
Rumors suggest Apple will release refreshed versions of the iPad mini and iPad Pro models in the first half of this year, potentially as soon as this month, and a new leak today has provided us with a possible preview of what to expect in terms of the devices' overall design and camera prospects. Tech leaker and Apple blogger Sonny Dickson this morning shared images on Twitter showing dummy ...
iMessage Android featured

Apple's Rationale for Not Bringing iMessage to Android Revealed in Legal Documents

Friday April 9, 2021 2:22 am PDT by
It's no secret that Apple sees iMessage as a big enough selling point to keep the service exclusive to Apple devices, however new court filings submitted by Epic Games in its ongoing lawsuit with the company reveal just how Apple executives have rationalized their decision not to develop a version of iMessage for Android. Apple clearly recognizes the power that iMessage has to keep users...
fake airpods 3

Counterfeit 'AirPods 3' Hit the Market Prior to Official Announcement

Friday April 9, 2021 2:45 am PDT by
Apple is expected to launch the third iteration of AirPods in the third quarter of this year. Rumors and reports suggest the new AirPods will feature an updated design more in line with the AirPods Pro, but lacking in "Pro" features such as active noise cancellation. Despite AirPods 3 not yet being officially announced by Apple, counterfeit products of the unreleased earbuds have already hit ...
nba tracking prompt orange

Two-Thirds of iPhone Users Expected to Block Ad Tracking

Friday April 9, 2021 7:19 am PDT by
As many as 68 percent of iPhone users are expected to deny advertisers permission to track them thanks to Apple's App Tracking Transparency feature, in what is beginning to look like a significant blow to the advertising industry (via AdWeek). With the launch of iOS 14.5, apps will have to receive explicit user permission before accessing an iPhone's advertising identifier or IDFA, which is...
iPhone 13 Battery Life Feature

DigiTimes: iPhone 13 Pro Models to Feature 120Hz ProMotion Refresh Rate and 15-20% Less Power Consumption

Friday April 9, 2021 12:52 am PDT by
The two premium "Pro" models of the upcoming iPhone 13 lineup will be equipped with a low-power LTPO display, enabling the iPhones to have a 120Hz refresh rate, according to industry sources cited by Taiwanese publication DigiTimes. According to today's paywalled report, Apple suppliers Samsung and LG Display are in the process of converting parts of their production capacity to produce LTPO ...
ipad pro and macbook pro

iPad and MacBook Production Reportedly Delayed Due to Global Chip Shortage

Thursday April 8, 2021 2:31 am PDT by
Apple is facing a global shortage of certain components for some of its MacBook and iPad models, causing the Cupertino tech giant and its suppliers to postpone production of the products, according to a new report from Nikkei Asia. According to the report, MacBook production is being hindered due to the shortage of chips mounted onto the circuit board before final assembly, which is a key...
ehric

iPhone 12 Mini Missing From Top 5 Best Selling Smartphone List of January 2021

Friday April 9, 2021 4:58 am PDT by
According to market data compiled by Counterpoint Research, Apple's smallest iPhone since the 2016 iPhone SE, the iPhone 12 mini, struggled to obtain a spot in the top five list of best-selling smartphones in January of this year. According to the market data, the iPhone 12 mini came in eighth place for the best-selling smartphone worldwide in the first month of the year. However, the iPhone ...
tmobile 5g modem

T-Mobile Launches Unlimited 5G Home Internet for $60/Month

Wednesday April 7, 2021 2:18 pm PDT by
T-Mobile today hosted an Un-carrier event where the company announced the launch of a a new 5G home internet plan, which is priced at $60 per month and offers unlimited data. The service is available to more than 30 million Americans across much of the United States, including 10 million households in rural areas not typically able to access reliable broadband. Connectivity will be either 4G ...
apple find my network

Apple Announces Find My Network With Support for Third-Party Devices

Wednesday April 7, 2021 10:06 am PDT by
Apple today announced the launch of its Find My network accessory program, which is designed to allow third-party Bluetooth devices to be tracked in the Find My app right alongside your Apple devices. According to Apple, the first accessory companies to take advantage of the new Find My integration include Belkin, Chipolo, and VanMoof, with devices set to be available beginning next week. ...