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dmk1974

macrumors 68020
Original poster
Sep 16, 2008
2,467
524
I got a new iPhone 12 from T-Mobile today. I usually just move the SIM from the phone I am replacing into the new phone and good to go. The "new" SIM that came in the 12 I just pop out and leave in the box just in case.

Since these are 5G, is there any reason that I need to activate this new SIM card? Or just fine with trransferring over the old one? Thanks.
 

mgmusicman94

macrumors 6502a
Nov 16, 2008
871
240
If you linked your T-Mobile account during purchase, the included sim will automatically activate.
 

antnard1

macrumors member
Jun 18, 2009
31
8
I'm not sure but I am trying to activate my new 12 Pro using the normal wizard and it has been spinning on "It may take a few minutes to activate your iPhone." for over 20 minutes...
 

dmk1974

macrumors 68020
Original poster
Sep 16, 2008
2,467
524
You need to use the SIM that came with the new T-Mobile phone.
Why is that? I actually did the initial setup with the SIM that came with the new phone, and while it certainly showed it was on the T-Mobile network, it did not list a phone number in the iPhone settings.

I then popped in the SIM transferred from the old phone and it all seems fine. Will something change perhaps?
 

Apple_Robert

Contributor
Sep 21, 2012
35,614
52,370
In a van down by the river
Why is that? I actually did the initial setup with the SIM that came with the new phone, and while it certainly showed it was on the T-Mobile network, it did not list a phone number in the iPhone settings.

I then popped in the SIM transferred from the old phone and it all seems fine. Will something change perhaps?
It is my understanding, unless something has changed, that when buying from the carrier, you need to use the SIM that came with the phone for activation purposes. In addition, make sure the new SIM supports 5G. You want the R15 (2020) SIM.
 

dmk1974

macrumors 68020
Original poster
Sep 16, 2008
2,467
524
It is my understanding, unless something has changed, that when buying from the carrier, you need to use the SIM that came with the phone for activation purposes. In addition, make sure the new SIM supports 5G. You want the R15 (2020) SIM.

Thanks. That makes sense for the R15 sim to get full 5G.
Since the SIM card that come with the new phone appears to not be activated, do I just text them or is there a website to enter the SIM number to tie it to the phone number?
 

Apple_Robert

Contributor
Sep 21, 2012
35,614
52,370
In a van down by the river
Thanks. That makes sense for the R15 sim to get full 5G.
Since the SIM card that come with the new phone appears to not be activated, do I just text them or is there a website to enter the SIM number to tie it to the phone number?
You can use the T-Mobile app to contact support in real time. The rep can get it activated for you.
 

dmk1974

macrumors 68020
Original poster
Sep 16, 2008
2,467
524
Thank you. I found the section under my account settings after I logged in. Pretty easy process (after I took a zoomed in photo of the SIM...I can't read that small!).

No difference in speed tests though after making the change. Oddly, my LTE speeds at my house (which were always great) are still faster. Maybe 5G is better in other areas?
 

buckethead

macrumors member
Oct 20, 2008
82
48
No difference in speed tests though after making the change. Oddly, my LTE speeds at my house (which were always great) are still faster. Maybe 5G is better in other areas?
5g at my house is under 10MB and LTE is 75ishMB. Ran an errand to return a case to Apple and a couple of miles away 5g was at 250MB. Ended up chatting with t force and they opened a ticket to have engineering look into the slow speed at my house. Not a big deal to me, but interesting to see them open a trouble ticket on it.
 
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