Household energy bills will rise by £111 a year from April after regulator Ofgem increased its price cap by 6.4%.
A typical home will now pay £1,849 annually, or £9.25 more per month.
The cap, which limits what suppliers can charge per unit of gas and electricity, affects 22 million homes in England, Scotland, and Wales.
Ofgem said the increase was driven by rising wholesale gas prices and inflation.
Standing charges - fixed fees for energy supply - will rise for gas but drop for electricity.
The next price cap review is in July, with analysts predicting a possible decrease. Ofgem has advised customers to consider switching to a fixed tariff to manage costs.
How the cap works and why it was introduced
The energy price cap was introduced by Ofgem in 2019 to protect consumers from being overcharged by energy suppliers. It does not cap total bills but limits the maximum price per unit of gas and electricity that suppliers can charge.
The actual bill a household pays depends on how much energy they use.
The cap is reviewed every three months and is based on the cost of buying wholesale gas and electricity, network maintenance, and supplier operating costs. It was created to prevent excessive charges for customers on default tariffs, who often paid higher rates than those on fixed-term deals.
During the 2022 energy crisis, the cap helped control price spikes, though government support was also needed to keep bills manageable.