Four in ten households are entering the winter with credit of more than £80 on their energy accounts but the vast majority just let it go, new research shows.
About half Britons opt to pay for their gas and electricity by monthly direct debit as it often means getting a discount on the bill.
However, the amount they end up paying is sometimes higher than their consumption, especially at the end of the summer or if they fail to provide regular meter readings, research shows.
The average overpayment across the UK was £85 this month, but a quarter of households overpaid by more than £100, a survey of 2,000 people by comparison website GoCompare has found.
This means that if the findings are applied to the UK population, energy providers could be sitting on a £928million cash pile in overpayments.
In spite of this, hardly any ask for a refund, with only 9 per cent of households actually being organised enough to take the step.
In fact, 39 per cent of households who overpaid bills said they left the money in the account to knock-off future bills.
‘[…] Because of the way direct debits are calculated, some customers may end up paying too much – particularly by the end of the summer when energy usage has been lower,’ said Ben Wilson from GoCompare Energy.
‘An easy way to help avoid building up a surplus on your energy account is to ensure you provide your gas and electricity provider with regular meter readings and, to read your bill when it arrives,’ he added.
The research also revealed wide regional differences in overpaid bills.
Households in London were the least likely to overpay bills, with less than a third in such a situation, while those in Yorkshire and Humberside top the list with nearly half having overpaid their energy bill.
On average, people living in the North East make the largest overpayments at £103, while those those in the East Midlands the lowest at £63.60.
Customers who find they have paid for more energy than they have used can leave the overpayment on their account to offset against future bills.
The big six energy providers – British Gas, EDF Energy, E.ON, Npower, Scottish Power and SSE – have direct debit policies which cover refunds.
‘Typically, these companies conduct annual reviews of DD accounts and, subject to an accurate meter reading, automatically refund overpayments of £5 or over,’ the report said.
‘However, customers with overpaid bills are entitled to ask their supplier, at any point in the year, for a refund. Providers are obliged to refund overpayments unless there are reasonable grounds not to do so.’
The report comes as the energy regulator warned that over half households end up paying more for gas and electricity because they do not engage with the market.
Publishing its annual report, Ofgem said 60 per cent of energy customers remained on poor value ‘default’ tariffs, which can be £300 more expensive a year than the cheapest deals.
A similar proportion of households never switched supplier or have switched only once, leaving them paying far more than those who engage with the market.
Ofgem also found that while bills have dropped since their peak in 2013, they are still higher in real terms than they were 10 years ago.
While the proportion of households in fuel poverty had remained stable since 2003, they were in greater need because their bills were higher.