Swap SIM card from iPhone 4 to iPhone 6 at&t?

[Hillshock]

I'm selling my iPhone 6 to a friend who has an iPhone 4 (or iPhone 4c?). We are both on AT&T. She asked that I help her set it up. I know to back hers up in iTunes then use that backup to transfer her data to the iPhone 6.

Regarding phone device, would I be able to just switch out the SIM card from her iPhone 4 to the iPhone 6? Are the SIM cards the same size? Or are we going to have to call ATT&T? Thanks in advance for your help!

 

[dictoresno]

She can do an iCloud backup instead of an iTunes one if she wants. That's my preferred method.

And no. She will need a new nano SIM card from AT&T. The iPhone 4/4S took a larger sized SIM card. Plus, she will need the new one to be able to access LTE on her new iPhone 6. Once she has your phone, she can walk into any AT&T store and get a new SIM card on the spot and they will switch the ICCID on the SIM to her account.