Five of the ‘big six’ suppliers – EDF, E.ON, Npower, Scottish Power and SSE – have hiked prices since the start of the year. Only British Gas has frozen prices.

Customers on standard variable tariffs with suppliers that have hiked costs will see their bills rise by £80 each on average, analysis by comparison site MoneySuperMarket found.

The extra £80 could buy an additional 600 kWh, which could power an LCD TV for two years, a microwave for six years, a vacuum cleaner for eight years or a low energy lightbulb for 30 years.

Households supplied by EDF, E.ON, Npower, Scottish Power and SSE in the East of England will be worst hit by the hikes, which range from 1% to 10%, paying an average of £88 each after the rises take effect.

This means customers on standard variable tariffs in this area will typically pay £1,254 per year.

Almost a quarter (23%) of households on ‘big six’ tariffs in this areas are with Npower, which announced the highest price rise of 10%. A third are with Scottish Power, which upped prices by 8%. As a result, the comparison site said these households could save £388 by switching to a cheaper fixed rate tariff.

Households in North Wales, Merseyside and Cheshire, where the majority of households on ‘big six’ tariffs are with EDF, which raised prices by 1%, will see the smallest price hikes, at an average of £58.

Nationally, households impacted by the price rises could save almost £400 by shopping around and switching providers, which could save a collective £7.4bn.

British Gas announced a prize freeze until August 2017 and while its customers may feel lucky to have escaped a price rise, those on its standard variable tariff typically pay £1,174 annually which is 34% more than those on the cheapest fixed deal on the market.

Stephen Murray, energy expert at MoneySuperMarket, said: “The message is loud and clear for the millions of people hit by big six price rises: shop around if you’re on a standard variable tariff, or if you’re on a fixed deal that’s coming to an end. Collectively, customers could save £7.4bn by standing up to price rises and shopping around – that’s well worth the seven minutes it takes to switch deals.”