Can I Transfer A Sim Card In A Contract?

So i'm in a contract with the iPhone 4 and i was just wondering if i could take the sim card of that phone and put it on the iPhone 5.
Will it do anything to my contract?
Will 4G count as cellular data?

You can take the sim card out and put it in a new phone and it will work like a charm. That doesn't work with a flip phone to a smart phone unless you are paying for Internet on the flip phone because you have to pay extra for the smart phone. But you have an iPhone 4 so moving it to a 5 should work. The only thing I'm not sure of is that 4G will work. I'm like 99.9% positive it will work though. This won't affect your contract it will still end on the day it is supposed to end and they won't say oh you have an iPhone 5 and you should have a 4 your contract is invalid now.