"The proposed licence condition will help give customers peace of mind that the amount they are being asked to pay is based on their likely energy use."
The announcement follows a large amount of protest over energy companies holding onto over-payments made by customers.
Garry Felgate, chief executive of the Energy Retail Association, said that all energy firms in the UK have signed up to a Commitment on Direct Debit Arrangements, which outlines the refund process.
Customers unhappy with their current provider could always turn to the internet and price comparison sites to find a new supplier and potentially a better deal.
Ofgem also called on energy firms to cut the cost of electricity and gas supplied to their customers in the wake of wholesale price declines.
Click here to run an energy price comparison, and see if you could be paying less for your gas and electricity.