A sharp rise in energy bills in 2006 could force an extra 250,000 households into fuel poverty, the energy price comparison website uSwitch has warned.
The cost of energy is expected to rise in 2006
uSwitch based its calculation on British Gas raising prices by a widely predicted 15% in 2006.
Households which spend more than 10% of their income on heating and power are deemed to be in fuel poverty.
According to the Department of Trade and Industry (DTI), 1.5 million UK homes currently suffer fuel poverty.
Last June, British Gas warned customers to expect price hikes in 2006 because of rises in the wholesale cost of gas and electricity.
Since then a host of gas and electricity companies have raised their prices.
uSwitch said higher energy costs made it "highly unlikely" that the government would succeed in its objective of ending fuel poverty by 2016.
"It is a worrying time for vulnerable customers, with record price hikes expected to be announced and a colder-than-average winter forecast," Ann Robinson, director of consumer policy at uSwitch, said.
"We are increasingly aware that more vulnerable customers are at grave risk of falling into fuel poverty," Ms Robinson added.