Do I need a different SIM card for an iPhone 5?

I have an Orange contract ut don't like the android phone I have. I was going to buy myself an iPhone 5 but do I need a new SIM card to go with it or would the one I currently have fit?

Yes, you will need a NANO SIM in order for it to fit into the iPhone 5. Feel free to contact your carrier (Orange) and simply ask to change the SIM, and stick with the same number.

And what type do you have now?

The iPhone5 needs a nano SIM (smallest of 3 sizes)
Orange will happly provide you one if you ask…
(worst is that you pay 10 pounds for a replacement,
but getting a free PAYG one off their website and then updating it using their website
-> Change SIM card
will do it - takes 1-2 mins max usually

you could just ring them and they will send a replacement one for your "damaged" one.

Local phone shops can cut the big one down with a tool
but they sometimes are still too thick and get jammed.
So a new one might be better