Four UK energy suppliers - including three of the 'Big Six - have agreed to automatically refund customers in credit on their accounts.
SSE, British Gas, EDF and First Utility have all confirmed they will now refund any such customers who pay their bills by Direct Debit. Fellow energy supplier, E.On, had already previously agreed to the arrangement.
A number of energy consumers pay bills based on estimates on their gas and electricity usage. Of course, estimates do not always present accurate usage figures and meter readings are then used to confirm exact usage.
Currently customers who find their usage below estimates then need to contact their energy firm for a refund on the amount they have overpaid.
Under the new scheme however, any credit over £5 for the 'Big Six' firms' customers, and £10 for First Utility customers, will be refunded by Direct Debit without the need for a formal request.
Minister for energy and climate change, Greg Barker, said: "This is important and welcome news for the 55% of energy customers who chose to pay by Direct Debit."
Which? executive director, Richard Lloyd, added: "It's welcome news that five energy companies have seen sense and will stop hanging on to customer's money when they're in credit.
"The other suppliers should take note and follow suit."
Two of the 'Big Six' energy suppliers have refused to join the new scheme however as neither Scottish Power nor npower have opted to join.
A spokesperson for npower explained: "We've had feedback that refunding very low amounts isn't worthwhile and we also know many people like to keep their account in credit."
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