Do I have to transfer my SIM card from old iPhone to the new one?

sberman wrote:

I have had fourteen iPhones and never once transferred a SIM card.

I've been using the same SIM since my iPhone 6. I've got to agree with Johnathan on this. It's by far the easiest way to transfer the cellular plan.

jrc611 wrote:

hmmm - everything seemed to transer over automatically so that is why I'm wondering

Your data is not stored on the SIM, it's stored in iCloud. All the SIM does is connect your phone to your carrier. If you don't transfer the SIM, you'll need to change the SIM number in your account by contacting your carrier. They may have a self-serve option if you sign into your cellular account online.

IdrisSeabright wrote:

If you don't transfer the SIM, you'll need to change the SIM number in your account by contacting your carrier.

I believe this is why you prefer transferring your SIM card.

In my case, I’ve always been with AT&T. When I order a replacement iPhone from Apple online, I am asked which carrier and answer “AT&T”. I can then submit my telephone number and some personal identifying information, and, lo and behold, when the new iPhone arrives, it is preset to expect to be placed in service using my telephone number, and the service switches to the new iPhone easily and quickly as part of the setup process.

You can.

It's the easiest way to use it with your current cellular plan.

jrc611 wrote:

do i have to transfer my sim card from old phone to new phone?

I have had fourteen iPhones and never once transferred a SIM card.

IdrisSeabright wrote:

I've been using the same SIM since my iPhone 6.

I believe if you would like 5G service on one of the current generation iPhones, you would need a new SIM.

Can you make and receive calls? If so, Apple may have done it for you.