Can I upgrade my Iphone early?

I currently have the Iphone 3G and it's been 1 year since I've had it, i know you have to have a 2 year contract but the Iphone 5 has come out and the iphone 4 is super cheap. Can I upgrade early?

Added (1). I want to upgrade to the 4, not 5

You should upgrade if you really want an Iphone 5, and if you can afford all the expenses toward it. If you really want one then get one. If i were you i would not wait another year.
Hope this helps!

Most likely no unless you pay the 700 dollars or whatever for the non -contracted phone. Call your carrier just in case to be sure and good luck!

The promotion on the iPhone 4 is that it will only cost you 99 cent with contract and/or upgrade. I have AT&T and literally just got off the phone with the operator. I ordered the iPhone 4. My upgrade was due for november but they didn't mind skipping it.AT&T is very easy going and they always work with you. I've used my upgrade at a max of 3 months early. Even so, you can always call them up and speak to them. I'm pretty sure they will work something out.