Update October 20: As we wrote before, it seems that Apple is adding support for 5G with dual sim with a software update. MacRumors has sources from the American provider Verizon heard Which Apple this fall one iOSupdate so you can still use 5G if two SIM cards are active at the same time. For now, the dualsim only works with 4G connections.
Original article October 19
Of iPhone 12series are the first iPhones with support of 5G. Also with the Dutch providers will be 5G supported on the 700MHz frequency. The iPhone 12 also supports the dualsim function of the iPhone. But if you want to combine 5G and dual sim, you may be disappointed. A page of the Apple Sales FAQ would show that when using dual SIM both SIM cards fall back to 4G speeds.
‘No 5G when using dualsim on iPhone’
That discovery was made by Reddit user ccthrow1, which would have access to Apple’s sales page. This website is for retailers only, where they can log in with a special one Apple ID. On that page there is an FAQ about 5G, asking whether 5G works with dualsim. The answer to that is as follows:
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.
So if you have two numbers on the iPhone 12 (a private and business number) and they are both active at the same time (so that you can be reached on both numbers on the same device), you cannot use 5G. 5G has been disabled for both numbers and is therefore falling back to 4G. This happens even if both providers support 5G on the number.
The FAQ also shows that 5G does work if you only have one e.g used, as long as you don’t have a physical SIM card active at the same time. This also applies the other way around: if you only use a physical SIM card (and therefore no eSIM), you can also simply use 5G (with a suitable provider and subscription).
At this point, we are still flagging this post as a rumor, as it is not yet available on any public page of the Apple website. We have checked with a provider whether this is indeed the case.
May be fixed with software update
According to the Reddit user, this is a temporary problem. Apple would release a software update at the end of this year that will add support for 5G to dualsim. It wouldn’t be the first time that Apple later expanded the dualsim function. Originally iMessage and FaceTime only available for one of the two lines, but in iOS 13 support for both lines has been added.