The previous deadline had been 2020 but industry and consumer groups had called that target “unfeasible”.

Smart meters are meant to save people money on their gas and electricity bills by providing suppliers with accurate meter readings, bringing an end to estimates.

Suppliers must offer all households in England, Wales and Scotland a smart meter by the roll-out deadline, but customers are not obliged to have one installed.

While smart meters promise to cut people’s bills, many households have reported technical issues with their devices.

Problems include smart displays not working, devices ceasing to function entirely and first generation meters (SMETS1) losing smart functionality when a household switches energy supplier.

Gillian Guy, chief executive of Citizens Advice, said: “Extending the smart meter rollout deadline is a common-sense move that is good news for consumers. It’s been clear for a long time that the 2020 deadline wouldn’t be met and today’s announcement finally recognises that reality.

“This new deadline gives suppliers time to fix ongoing technical problems and make sure customer service isn’t sidelined as the rollout continues.”

Citizens Advice said it had received reports of suppliers using aggressive sales practices to convince people to have a smart meter installed to meet their targets.

Switching problems

Recent research by automatic switching service Look After My Bills found eight energy companies, including two of the Big Six, were still rolling out outdated smart meters even though the government deadline for ending these was March 2019.

According to the switching firm, only 1.9 million of the 15.97 million smart meters installed in people’s homes have been updated to second generation meters that continue to work when you switch.

Lily Green, head of research at Look After My Bills, said: “At last the government has faced up to the truth and admitted that the smart meter rollout is years behind.

“It’s been an open secret in the energy industry that the smart meter deadline will be pushed back.

“Suppliers are miles off from installing smart meters in all homes, with around 35 million homes still without a smart meter.”