deposit for utilities

When setting up utilities (gas, electric, telephone) are you required to pay a deposit before they connect you? I know every time we move to a new area they always require some awful amount of a deposit and then give it back to you a year later. Would it be a good idea to bring reference letters from the utilities companies here in the States, will that help things go a bit smoother in the UK ?

Thanks
Cad

I worried about this when we moved into our own place in May last year.  The good news is we never had to pay a deposit on any of our utilities.  Whether this is universal throughout the UK, I guess I will leave others to give their experiences on.  We didn't pay any deposits and I even asked and was always told it was not required.