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."
Make sure you're not paying too much for your energy - compare gas and electricity prices now at energyhelpline.com or call 0800 074 0745