What happens if I put the SIM card of a non smartphone into and iPhone?

I use AT&T and I have an HTC but it isn't a smart phone. So if I cut the SIM card into a nano SIM card, which is used for iPhones, and put it in an iPhone 4S, will the phone work? Also I do not use data on my phone, only texting and calling and I'm not telling the AT&T people because they would make me get an iPhone which I can't do until my contract ends next year or ill have to pay 300 dollars.

Your cut down sim would work fine, but AT&T would see your now using a smartphone and adjust you bill by adding a data plan. The phones iemi/esn will let AT&T see what device your using, sorry dude.

Whoa… Isn't the HTC a smartphone? I believe that the older ones ran a windows version and then they went to android.
I double checked and found http://en.wikipedia.org/...g/wiki/HTC