“Big six” energy supplier SSE is increasing prices by an average of £76 a year in a hike affecting more than two million customers.
The price changes – a 5.7% rise for gas and 7.7% for electricity bills – mean a typical dual fuel customer will see an increase of £1.50 each week.
SSE blamed the price hike, which comes into effect on 11 July, on rising wholesale and government policy costs and said it would impact 2.4 million customers.
Households with a pre-payment meter or on fixed-price or vulnerable customer safeguard tariffs are not affected.
The company also announced it will remove its £6 per fuel, per year paperless billing discount when the changes come into effect.
It is the last of the largest energy companies to reveal price changes following a series of hikes announced by rivals British Gas, EDF, Scottish Power and npower, and the scrapping of a customer discount by E.On that will also effectively mean higher bills.
They have blamed the government’s planned introduction of a cap on standard variable tariffs for increasing prices.
More than nine million households will be hit when the tariff rises from the energy firms come into effect in the summer, which economists have said will likely push up inflation.
Stephen Forbes, chief commercial officer of 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.”
SSE is currently under regulatory scrutiny over a planned tie-up involving npower.
Last November, npower owner Innogy agreed a deal with SSE for the two companies to demerge their UK supply arms so that they could join forces to create a new player.
The deal, which would reduce the big six to five, is being investigated by the Competition and Markets Authority (CMA), which earlier this month referred it for an in-depth inquiry to report in October.
All energy firms have been facing pressure for some time over the way they treat customers.
In February, MPs called for a cap on the price of gas and electricity amid fears consumers are being “ripped off”.
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