iPhone X Selling Old iPhone - Original SIM Card in New iPhone

[southerndoc]

I took the SIM card out of my iPhone X and put it in my 11 Pro because AT&T said I had to go to the store to transfer service to the new iPhone with new SIM card.

I'm about to sell my X (without the SIM card). When the buyer purchases it and uses a new SIM card, will it affect the service on my 11 Pro at all? The reason I ask is because the IMEI number hasn't been changed to the 11 Pro's IMEI number (at least not to my knowledge unless the SIM card automatically sends this to AT&T).

 

[Apple_Robert]

Shouldn’t be a problem.

 

[Reno Raines]

Nope no problem at all. I have done that many times.

 

[Heroine Lover]

IMEI Numbers are unique to each phone and never transfer to a new phone. When you get a new phone, that phone has a different IMEI than your old one. Just be sure to properly reset and wipe clean the phone you’re selling, and you won’t have any issues.

 

[JayMosEnvied]

When I went to buy my pro max at apple the rep took my sim card from my 7 plus and put it in the max and worked like nothing happened. Like the poster above me said before selling just reset to factory. If you have AT&T request to get the phone unlocked. They approved me within 5 minutes.

 

[Martyimac]

I did that yesterday, in the store, with my Verizon SIM and it went through almost instantly.

 

[southerndoc]

Thanks for all the info. Confirmed what I thought.

On another note, I have FirstNet via an eSIM while AT&T is my primary provider. When I upgrade phones down the road, will the eSIM automatically transfer my plan or will I have to contact FirstNet (AT&T) to get it to transfer?