Householders are set to face bills of up to £1,400 a year from this autumn, which could prompt many to switch gas deals and look for cheap energy alternatives.
In the last week, two energy suppliers had cheap fixed tariffs expire - ScottishPower ended its Online Energy Reward capped deal as well as its Fix 'n Flex plan, while npower withdrew its Go Fix 2 package.
Scottish and Southern Energy also implemented a new tariff - the Price Fix 7 - which locks in prices for three years but costs more than £1,300 (£1,307) a year.
Mark Todd, director of energy comparison site energyhelpline.com, commented: "This is a sign of things to come as the big players in the market protect their profit margins in the face of rising wholesale prices."
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