As Britain enters a week of sub-zero temperatures, it has emerged that thousands of British Gas customers with prepayment meters are still waiting for government help, with a third yet to receive any of their monthly £66 energy support vouchers. According to a survey of 5,500 people by MoneySavingExpert.com, about 20% of all households with a traditional prepayment meter – which include some of the poorest and most vulnerable – are yet to receive vouchers from their energy suppliers. The scheme runs from 1 October to the end of March, and is meant to provide£400 in help across the six months for all households in the UK, paid in monthly instalments. While the money is automatically credited to the accounts of customers who pay by direct debit, the 2m homes with prepay meters need a paper voucher sent by post by their energy supplier, which is scanned at the shop or Post Office counter when topping up. So far two vouchers should have been sent, for October and November, totalling £132. British Gas was the worst performer, according to respondents, with more than 31% of customers who responded saying they still hadn’t received their October or November voucher, more than any other firm. SSE and Scottish Power also scored poorly, with a fifth of their customers (23% and 20%, respectively) saying they have yet to be helped. The energy suppliers are supposed to have already sent out the first two monthly payments. The vouchers will expire after three months, meaning October vouchers will be invalid from 3 January, while November’s expire on 5 February. As the Guardian reported last week, about 1.3m vouchers have either been lost, delayed or unclaimed. Wrong names and addresses on databases, and a reluctance of people in debt to open bills, partly explains the numbers. However, delays at the power firms themselves have also been a big problem. For many, receiving the vouchers will be the difference between keeping warm or not over the coldest week of the winter so far. Overnight lows of -10C are predicted in northern Scotland, with snow and ice in Wales, Northern Ireland and the east coast. In England overnight lows of -4C and daytime temperatures close to freezing are forecast over the next few days. Martin Lewis, founder of MoneySavingExpert.com, said: “This is simply not good enough from British Gas. The country’s biggest energy provider is withholding crucial funds from many of the poorest in society, as we head into winter amidst an energy crisis. Scottish Power and SSE don’t seem to be that much better either. “Things need fixing and that must happen with a sense of urgency. The government effectively subcontracted energy firms to provide an energy welfare payment, and these firms are failing in their duty to do it. Worse still, it’s those on old school prepay meters – which are often installed in the homes of some of the most vulnerable – whose shoulders this falls on.” British Gas said it had issued all October and November vouchers, and customers without them should get in touch. “To ensure our customers can contact us for support and advice, we’ve recruited an additional 700 people over the summer. We don’t always get everything right, but we are constantly looking at how we can do more,” it said. Scottish Power said the vast majority of customers are receiving their payments on time.