Can you put pay go sim into pay monthly iPhone 5?

Ok I order iPhone 5 for £30 month I put my pay go sim in to the iPhone 5 it worked will still go over £30 month if not using my sim will or will it still up if using my iPhone 5 with pay and go sim

Yes, with my company you can. You just need to get a pay go and ask them too exchange it for a Micro SIM. A regular sim will not fit the iphone 5.

You can cut regular sim card with sim cutting tool and use it in your iPhone

Yes, though your contract iPhone 5 might be locked to your network - if the PAYG sim is the same network it will be fine