The company becomes the last of the "big six" energy companies to announce early summer price rises. : SSE has become the last of the "big six" energy companies to announce early summer price rises, with a 6.7% average increase in gas and electricity bills. The move will see gas prices rise by 5.7% and electricity prices go up by 7.7% on 11 July for SSE customers on variable deals. The company said the price rise was the result of increasing costs "largely outside our control".