Energy companies are charging their established customers higher prices, a progress report on competition in the industry shows.
The Competition and Markets Authority found that 95% of dual fuel customers on standard variable tariffs could have saved £158 to £234 a year if they had switched provider between 2011 and 2014.
The regulator said consistently higher bills for standard rate customers indicated that the big companies were charging long-term customers more than necessary.
The CMA said: “We have observed that the six large energy firms have consistently charged higher prices for the SVT for gas and electricity compared with non-standard tariffs, which provides some support for the view that these suppliers can segment the market and price discriminate.”
The CMA launched its investigation last July after a referral by the energy regulator, Ofgem.
The big six energy firms – SSE, Scottish Power, British Gas owner Centrica, RWE npower, E.On and EDF Energy – control about 92% of the UK’s energy supply market.
Energy prices are high on the political agenda after Labour leader Ed Miliband used his 2013 conference speech to say the party would freeze prices if it won the election. High energy costs have contributed to the squeeze on household budgets.
The CMA said it had not yet reached any conclusions. It will publish its provisional findings in May.
