Energy giants have not passed on dramatic falls in wholesale prices meaning customers are overpaying by the tune of £120 a year, a price comparison site has claimed.
Over the last two years, wholesale gas prices have tumbled 36% while electricity has come down 20%, according to Energyhelpline.
"There is a huge mismatch between wholesale price cuts and what savings are being passed on to the customer," the company said in a release.
"This points to the fact that it is the energy giants who are benefiting the most at the expense of the consumer."
Its data suggested consumers could save an average of £275 by switching to the cheapest energy deal on the market.
It also called on customers to check prices at smaller independent suppliers, with nine of the 10 cheapest deals on the market being offered by suppliers outside of the traditional Big Six.
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