More than half a million households have fallen behind on their energy bills since February, taking the total number of billpayers in arrears to more than 2 million, according to Citizens Advice.
The consumer charity said an extra 600,000 households owed payments to their energy suppliers, with the coronavirus outbreak leading to record high redundancies this year.
On average, billpayers who have fallen behind on their payments owe their energy suppliers about £760 for electricity and £605 for gas, according to Citizens Advice.
The findings show that about 16% of homes that use energy prepay meters – or almost 700,000 households – have not been able to afford a top-up since March.
The new report, which is based on figures collected from large and medium energy suppliers at the end of September, is the first to show the scale of the financial struggle facing energy bill payers, many of whom are using more energy at home due to coronavirus restrictions.
Citizens Advice warned that financial woes were likely to deepen through the colder months and that an estimated 7 million households were expected to struggle to pay their winter energy bills this year.
Alistair Cromwell, the acting chief executive of Citizens Advice, said: “We’re heading into the coldest months of the year and the full financial impacts of the pandemic are still to be felt.”
The consumer watchdog published its findings alongside new research that shows declining levels of service among energy companies, many of which are struggling financially due to rising unpaid debt from customers.
Customer service standards were “more critical than ever” to help support billpayers, said Citizens Advice, but call waiting times for two-thirds of suppliers had increased and on average energy suppliers were failing to respond to a third of customer emails within two working days.
Energy suppliers have agreed to offer payment plans to help support customers as they struggle to pay their bills, and offer homes on prepay meters credit certificates so they are not left in the dark when they cannot afford a top-up.
The larger energy suppliers are understood to be pushing for the regulator to raise the energy price cap for the standard variable tariff from Spring so they can reclaim lost revenues from customers who are still able to pay their bills.
Ofgem, the industry regulator, said it had “strong protections in place for consumers” and expected customers to “be able to easily contact their supplier across a range of channels”.
“We closely monitor and engage with energy suppliers and will take appropriate action over poor customer service where needed,” the spokesman added.