Energy bills could reach £5,815 from next April as inflation is due to hit 18.6%, experts say.
Investment firm Citi thinks inflation will rise from 10.1% currently to above 18% in January 2023.
Citi has forecast that a surge in wholesale energy prices will lead to inflation “entering the stratosphere” in the new year, according to the Financial Times.
The company believes that the energy bill price cap could go up from £1,971 a year currently to £4,567 in January 2023 and £5,816 in April.
Consultancy Auxilione previously said Ofgem could set its price cap at £4,467 in January 2023, rising to £6,089 in April.
Consultants at Cornwall Insight, who correctly predicted the last big energy bill rise, expects the price cap to rise to £4,266 in January.
Citi chief UK economist Benjamin Nabarro said: "We now expect CPI inflation to peak at over 18% in January."
Other financial experts at investment firm Goldman Sachs and accountants EY said inflation would be at least 15% in the new year.
The Bank of England thinks inflation could be above 13% this year.
What is the Ofgem energy price cap?
More than 80% of British homes are now on energy deals limited by the Ofgem price cap, due to rise again on October 1.
Despite what its name suggests, the price cap isn't a limit on how much you pay for energy.
Instead, it sets a limit on the rates a supplier can charge for each unit of gas and electricity you use, for homes on variable-rate energy deals paying by direct debit.
The price cap also sets a maximum for the daily standing charge, which is what you pay to have your home connected to the grid.
The price cap is altered every three months, in January, April, July and October.
This means the next time it will be reviewed is in October, then again in January.
Ofgem first introduced the price cap in 2019 and it is based on a number of factors including the wholesale cost of power.
When will the price cap next change?
Ofgem is due to change the price cap again on October 1. This will then last until Jannuary 2023.
The energy regulator is due to reveal its new price cap for October on August 26.
What energy bill help is available?
Talk to your energy bill provider as soon as possible if you can't pay your bill - they might be able to put you on a payment plan or offer some sort of tailored support.
It's also worth asking them if you're definitely on their cheapest deal.
Many big energy firms have charitable hardship funds and grants that you may be eligible for if you’re struggling.
For example, the British Gas Energy Trust can be accessed by anyone - not just its customers - providing you meet the eligibility criteria.
If you’re over the state pension age, you may be eligible for the Winter Fuel Payment scheme, worth between £100 and £300 during the winter months.
