A “truly unprecedented” number of prepayment customers face having their gas and electricity cut off by the end of the year, new forecasts show.

In yet another stark example of the impact of the cost of living crisis, data from Citizens Advice suggest 21,604 households will have been unable to top up their meters by December.

By contrast, in 2021, 8,618 customers were unable to top up. It means if the 2022 forecast is correct, the number who can’t afford to top up will have more than doubled in the space of 12 months.

Already this year, Citizens Advice has seen 10,802 customers who are unable to afford their prepayment meters. That is more than 2019 (3,145) and 2020 (4,976) combined.

Citizens Advice said: “We're seeing a truly unprecedented number of people who can't afford to top up their prepayment energy meter, and therefore can't do the basics like turning on their fridge or heating their hob.

“By the end of June this year, more people had come to us than in each of the past three years.”

It comes as National Energy Action, the fuel poverty charity, said it is hearing many concerns from people on prepayment meters and credit meters.

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“There is a lot of fear about how people are going to survive the winter,” Maureen Fildes told BBC Radio 4’s Today programme.

As part of a previously-announced intervention by former chancellor Rishi Sunak, households will start receiving money off their energy bills from October, with a discount made in six instalments totalling £400.

Traditional prepayment meter customers will be provided with energy bill discount vouchers in the first week of each month - issued via text message, email or post - using the customer’s registered contact details.

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These customers will need to take action to redeem these at their usual top-up point, such as their nearest local PayPoint or Post Office branch.

Fildes, though, warned of a danger that people struggling to pay bills may ignore envelopes they fear are demand letters.

She urged customers to ensure that their contact details with their supplier are up-to-date - and not to ignore any post that comes through from their supplier.