Gas standing charges will be scrapped in England, Scotland and Wales, during 2027 “or as soon as possible after”, the chancellor said.
These fixed daily fees will be shifted onto the price of each unit of energy.
The Treasury calculates that 60% of households will gain an average of £45 a year, with lower users gaining the most – but not until after the projected big rise in bills in January.
Higher users – in the biggest houses but also large, low-income families – will pay more than they currently do.
The government wants to extend reforms to electricity standing charges later.