Go dual fuel and DD for best deals

Also, you can challenge the amount you pay each month. Im with Scottish&Southern (southern Electric) and the hiked the gas price by £14 (40%) per month.

I was on the phone straight away asking them to put it back. You are entirely in your right to do this. It's advisable to be realistic though and not pay them £5 per month and end up with £1k bill at the end of the year

Just do it so that you are £5 in debt or credit.

Also take your own meter readings. It takes 5mins and will give you an accurate bill.