Five million households will be forced to spend at least a tenth of their budget on energy bills after the largest price rise since records began came into effect on Friday.
Bills will increase by an average of £693 a year to the cost for those on default tariffs after Ofgem’s price cap was lifted by 54 per cent.
The price rises will double the number of households in “fuel stress” – a term for those spending 10 per cent or more of their income after housing costs on energy bills – overnight from 2.5 to 5 million in England alone, according to the Resolution Foundation think tank.
A number of energy firm websites crashed on Thursday as customers rushed to take meter readings to avoid firms assigning current usage to April when rates are set to jump.