Martin Lewis has urged households who are thinking about fixing into an energy deal to act “as soon as possible”.
The MoneySavingExpert took to Twitter to explain how wholesale energy prices “have spiked” again over the last week.
He warned this could mean some gas and electricity firms will pull the cheapest existing customer fixes and replace them with more expensive deals.
A fixed rate tariff is where you agree to pay a certain amount for each unit of energy used for a set period of time.
But around 22 million families are on the standard price cap rate right now, due to a lack of cheap deals.
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“It's plausible energy firms will pull the cheapest existing customer fixes & replace with costlier,” explained Martin on Twitter.
“If you are considering fixing, my best guess is go ASAP.”
The latest warning from Martin saw the MSE founder advise households that they should only consider fixing into an energy deal that is no more than 35% higher than the current price cap.
This rises to no more than 40% more “if you very strongly value budgeting certainty”.
The bad news is, the latest MSE calculations show there are currently no fixes below these thresholds on the open market.
However, you might be able to find a tariff that is below 40% through your existing energy provider.
MoneySavingExpert has highlighted an E.on and E.on Next V14 one-year fix that is 30% more - but again, this is only available to some households that are already with E.on.
Two-year fixes are harder to predict in terms of value for money, as it is less certain how energy prices will fluctuate.
If you did want to fix for longer, MSE has flagged an EDF Energy two-year deal for existing customers that is 34% above the current price cap.
This is for the Fix Total Service Jun24v2 two-year fix.
The other tariff flagged by MSE is from So Energy, which is offering one and two-year fixes on its So Hibiscus deal that are both 40% about the current price cap.
The current price cap, which sets a limit on the rates a supplier can charge for each unit of gas and electricity you use, is £1,971 a year for those on a default tariff who pay by direct debit.
Ofgem is now predicting that the price cap could rise to £2,800 this October.
Energy consultant Cornwall Insight put the October price cap at the slightly higher £2,879, before rising to £2,907 in January, under new rules that mean the cap can be adjusted every three months.
Millions of households will receive a £400 discount on their energy bills later this year as families continue to struggle against the cost of living crisis.
The new support was confirmed as a replacement for the £200 "loan-not-loan" that would've needed to be paid back starting from 2023.
