When trading from one phone to another ,when do you transfer the SIM card?

And I transfer the sim card AFTER everything has been transferred over to the new phone. This way, I can take calls on the old phone without interrupting the transfer of data to the new phone.

However, either way as you suggest is fine.

For iPhone 12, I did NOT transfer the sim. I was advised (whether it really makes a difference I don't know) to use a newer Sim card which is provisioned for 5G service.

It doesn't really matter. My personal preference, for no apparent reason, to move the SIM card first.

Axel F.

You are welcome.

Axel F.

Yesterday, I purchased an iPhone 12 Pro Max which I didn't; need however wanted to have it. I transferred service from an iPhone Xs Max. You are correct about what you mentioned about a different SIM for 5G service. I bought my iPhone SIM Free and had to visit my carrier and activate the SIM for 5G. I then went home and didn't; have a choice but to install the newly activated SIM first in the new iPhone because service had been discontinued on the old SIM and iPhone.

It was still fun backing up and restoring from backup and then Face ID and apps with Face ID etc etc. You know, the same thing that we do every other or every year.

Axel F.

This year we bought our phones unlocked from Apple but we ordered choosing AT&T and our phone numbers with the order and when we got both phones, upon turn on, they activated immediately to our phone numbers and came already loaded with 5G ready sim cards. It was honestly awesome and so incredibly simple.

We got ours yesterday as mentioned. Both of us have iPhones with two lines each (Work and Home). The lines on the physical SIM cards were easy to activate. No one, including the carrier (store) knew how to transfer the eSIM lines from our old iPhones to new. I told them that I'd call the support team after we reach home. At home, on a whim, I just went into settings and chose Add a Plan and the iPhone prompted to switch the right eSIM line to the right iPhone. Went through a quick validation and it was done. THAT blew me away because of the speed and simplicity to transfer an eSIM line without any phone calls.

Axel F.

Haven't yet had a need to use eSim, but it sounds like it was painlessly simple!