AT&T SIM Card?

mrpacs

Well-Known Member
Oct 11, 2008
2,993
78
48
Connecticut
I had been a LONG time VZW user until Fall 2008 when I jumped ship and moved to AT&T/iPhone heaven. What exactly is the SIM card for and how do I use it? What do I do with my iphone SIM card when/if I sell my iphone? TIA.
 

DAB

Mod Emeritus
Oct 9, 2008
9,434
149
63
Louisiana
Some SIM cards can be moved to other phones, I know I've moved my Sim card into several phones, this brings all your service information and allows the phone to operate on the carriers network. No Sim no workie! If you change services then you can destroy the Sim card and move happily on to your new carrier.
 

mrpacs

Well-Known Member
Oct 11, 2008
2,993
78
48
Connecticut
So if I sell my 3G and take it's SIM card and insert it into the new phone, (3Gs perhaps). I would then take the SIM card from the 3Gs and put that into the old 3G? Can I sell my 3G without a SIM card?
 
Oct 10, 2008
644
11
18
Chicago
Yes, you can sell your phone without a SIM card. The SIM card is the registration for the phone to the network. Most phones have coding in them that will only work for that one network, or in your case only for AT&T. Do not include your SIM card when you sell your iPhone. I'm also certain that when you buy your new phone they will give you a new SIM card. It's just their SOP. (standard operating procedure)
 

sgip2000

Member
Oct 16, 2008
104
3
18
Hillsboro, OR
I have T-Mobile which also uses SIM cards.

The SIM card stores your phone number, contacts, carrier information, etc. The SIM card should stay with the original customer.

If you get a new phone, you can simply insert your SIM into the new phone.

When you get rid of your old phone, make sure you remove the SIM.
 
Oct 10, 2008
644
11
18
Chicago
The SIM card stores your phone number, contacts, carrier information, etc. The SIM card should stay with the original customer.

In some cases this is true, but not all. It does carry your carrier information but it won't always keep your contacts on there. Some phones store contact information on the phone itself instead of the SIM. Be aware of this because if you use your SIM in a new phone, not all contacts will transfer over.
 

sgip2000

Member
Oct 16, 2008
104
3
18
Hillsboro, OR
In some cases this is true, but not all. It does carry your carrier information but it won't always keep your contacts on there. Some phones store contact information on the phone itself instead of the SIM. Be aware of this because if you use your SIM in a new phone, not all contacts will transfer over.

Very true. I am only able to store a small amount of contacts on my SIM.
 

DAB

Mod Emeritus
Oct 9, 2008
9,434
149
63
Louisiana
My understanding is the new 3G(s) will be sent with a Sim card and you must use this card to activate it. In reading on several other forums it has been said you can't just use an old Sim. Still it makes no sense to me because if the other phone is a 3G and your plan will be the same, which particular iPhone model you have other than the original should not matter.

Lots of folks are doing swaps and have family members that are eligible for getting a new 3G(s) at the lower price and will giving their 3G or even original iPhone to another family member. I am sure AT&T is going to have a lot of fun with this.