Energy providers have urged customers to take meter readings before costs rise on Saturday, warning that they could be overcharged if they fail to do so.
If up-to-date figures are not provided, companies might charge the new, higher rate for energy used before 1 October.
Money expert Martin Lewis has urged people to jot down their readings. “That way you draw a line in the sand that says to your energy firm, I’ve only used this amount at the cheaper rate,” he said.
Wholesale gas and electricity prices have soared since Russia invaded Ukraine in late February, with consumers having to pay far higher energy bills as a result.
Liz Truss’s government decided to introduce an “energy price guarantee” in an attempt to help households weather the cost-of-living crisis.
Under the scheme, the average household energy bill will jump from £1,971 to £2,500, rather than the £3,549 the regulator Ofgem had envisaged.
However, actual bills, which are expected to be 96 per cent than last year, will still be determined by usage.
Frazer Scott, chief executive of Energy Action Scotland, urged customers to submit meter readings to avoid paying more than they needed.
“This week, every household across the UK must make sure it submits a meter reading to their energy firm to avoid paying a penny more than they absolutely have to when prices go up on 1 October,” he said.
Ahead of the last price cap rise on 1 April, hundreds of thousands of people rushed to submit their readings, with the increased demand causing websites to crash.
Most energy companies will allow customers a grace period to submit their pre-October readings, which will then be backdated. Those with smart meters will not need to notify their providers, as long as the devices are working correctly.
Despite the government’s support package, there are fears about how the most vulnerable will cope this winter.
Mr Scott, the boss of Energy Action Scotland, said: “Fuel poverty is at record levels, levels of energy efficiency improvements are simply too low to provide respite and financial support is just a sticking plaster on the deepest of wounds.
“As unit costs for electricity and gas push bills higher still in October, communities will suffer and take years to recover. Meanwhile the impact of fuel poverty will be felt on the NHS and social care system and lives will be needlessly lost.”
Research by comparison site Uswitch suggests that one in five households will have to reduce energy usage this winter to make ends meet, while 11 per cent of homes will be unable to cope with the additional costs whatever they do.
