The last of the “big six” power companies has announced it is raising its prices due to “sustained increases in wholesale and policy costs”.

SSE is putting its gas prices up by 5.7% and its electricity prices 7.7% higher, following in the footsteps of Centrica, EDF, Npower and ScottishPower, while E.ON has ended discounts and increased standard charges.

Stephen Forbes, Chief Commercial Officer at SSE Energy Services, said: “We deeply regret having to raise prices and have worked hard to withstand the increasing costs that are largely outside our control by reducing our own internal costs.

“However, as we’ve seen with recent adjustments to Ofgem’s price caps, the cost of supplying energy is increasing and this ultimately impacts the prices we’re able to offer customers.”

Which? says nine million customers could save cash

In the wake of SSE’s announcement, consumer group Which? published figures suggesting nine million “big six” customers could save up to £434 a year by switching supplier.

“Energy customers tired of being slapped with eye-watering energy bills can take the power back into their own hands and radically change how much they pay, simply by choosing a better deal,” argued Alex Neill, Which? Managing Director of Home Products and Services.

“Before the energy price cap comes into effect later this year, anyone still suffering on a poor value standard tariff should take five minutes to compare and switch as they could potentially save up to £434 a year.”

> See SSE's statement