How long until i can upgrade with AT&T?

I bought my iPhone 4S last November and I wanted to know how long I have to wait until I can get the iPhone 5.

A new iPhone costs $649 retail. When you buy a new iPhone on a carrier, you get it on a contract. In AT&T's case, you buy an iPhone for $199 (minimum) and agree to pay AT&T monthly for two years. If you cancel, you pay a large fee that would cover the time in what would have been your remaining term.

You can upgrade to iPhone 5 at any time; however, you'll pay more than $199 because you have a newer contract. You probably won't pay full price, but you'll pay around $400 for a new iPhone 5. You don't get an iPhone for full reduced price until 18 months after you start your contract, so you can get an iPhone 5 for full reduced price ($199 for a 16GB model) in May of 2013, about six months from now.