Consumers are facing rises in energy prices as suppliers move to cut special deals and discounts.
A number of the cheapest gas and electricity tariffs, such as npower's Go Fix 5, which was the cheapest fixed tariff on the market, have closed.
This is coupled with British Gas owner Centrica admitting fears of wholesale price rises, and smaller providers including First Utility and Ovo raising their standard tariffs in the last couple of weeks.
Energyhelpline.com director Mark Todd said: "Over the past month, there has been a bonfire of some of the best deals on the market.
"The outlook is very bleak and consumers need to act quickly if they want to snap up the cheapest deals or opt for a fixed rate tariff which will protect them from further price rises."
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