Carrier When you buy an unlocked phone from Apple...

[ssledoux]

Can you just put an active AT&T SIM in it and have it work, or do you have to actually activate it?

 

[noobinator]

If the sim is active, just pop it in.

 

[MultiFinder17]

Yup, just pop a SIM that's active in there and you're good to go. I usually buy my iPhones outright from Apple. No payments, and no 'upgrade/activation' fees from Verizon 🙂