The cheapest energy tariff for many has been pulled for new customers.
Ovo Energy has hiked the price of what price comparison site Energyhelpline.com says was the market-leading tariff from £855 a year, based on average consumption, to £926.
Ovo blames a rise in wholesale costs, which is the price power firms pay for gas and electricity.
Energyhelpline.com says the new cheapest deal, based on typical consumption, is Npower's Sign Online 18 at a typical £876 a year.
The news comes as tens of thousands of Npower customers are set to see their costs soar from next month (see the Npower price warning MSE news story).
Ovo founder Stephen Fitzpatrick says: "Wholesale prices have risen considerably since we last bought energy – rising by 20% in the last two weeks.
"To reflect this rise, we have returned our tariffs to the rates we were offering a month ago."
How to find the best deals
Households can sometimes cut their bills by hundreds by doing a comparison of the tariffs available and switching (see the Compare Gas & Electricity and Get Cashback guide).
Those languishing on their supplier's standard tariff or who get bills through the post are almost certainly paying too much.
While the cheapest online deals for typical users are less than £900 a year, those on a standard tariff typically pay around £1,200.
When switching, don't believe the hype from the major firms which often claim they have the cheapest prices. The energy market is complicated so determining which is the cheapest provider for you depends on where you live and how much power you use.
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