Households using prepayment meters have been urged to avoid missing out on £400 worth of support, with just a month left to claim.
All households were eligible for the Government’s Energy Bills Support Scheme, which paid £400 in six monthly instalments of £66 or £67 over the winter.
Prepayment customers – often some of the most vulnerable energy users – were paid in vouchers, but £130 million remains unclaimed.
Some customers did not receive the vouchers, while others have struggled to redeem them.
The government is coordinating with charities to promote Claim Your Energy Voucher Day in a last push to get the final round of energy support money used.
Adam Scorer, chief executive at National Energy Action, urged anyone who is on a prepayment meter to check if they qualify and to tell anyone they think may be eligible about the opportunity.
He said: "It may be the support that keeps their lights on, their oven cooking, their hot showers running, through the summer. It’s vital money at a time when it’s never been needed more."How to claim £400 prepayment meter energy support vouchers
Customers need to visit a post office or PayPoint with their Energy Bills Support vouchers and identification before June 30.
Any lost, missing or expired vouchers can be reissued, as long as they are redeemed by that date.
Those on a traditional prepayment meter who have not received the vouchers, or are unsure of how to redeem them, or need a voucher to be reissued, should contact their supplier.
Latest figures show the number of vouchers cashed in has reached an all-time high of 83%, with prepayment meter users so far claiming nearly £650 million under the scheme.
The figures, published earlier this month, show for the sixth month in a row, London had the lowest redemption rate, with more than 650,000 vouchers still unused at the end of March.
Around 25% of vouchers in both Scotland and the south-east of England are also yet to be claimed.
Energy minister Amanda Solloway said: "We’ve made huge strides in getting nearly £650 million from our Energy Bills Support Scheme out to prepayment meter customers, often in the homes that need it most.
"Today we are redoubling our efforts to reach anyone who still hasn’t claimed this help, and it’s fantastic to see so many join our final push to spread the word.
"Tell friends and family or anyone on a traditional prepayment meter to use their vouchers for up to £400 off bills before June 30 – there is still £130 million out there to claim."
Households using prepayment meters who use alternative fuels such as LPG, heating oil or biomass as the main way they heat their homes also have until June 30 to use their vouchers worth up to £200 in energy bills support.
Customers will have received these vouchers in the post from their supplier and should contact them if they have any questions.
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