Npower, British Gas and E.ON allegedly told people they could be charged for switching supplier at the end of a fixed tariff
Ofgem is looking into allegations that energy suppliers have wrongly threatened to impose exit fees on householders switching away from them.
The energy regulator confirmed it was talking to some of the big six energy companies after MoneySavingExpert (MSE) handed over a bundle of customer complaints on mishandling of such fees, which can be up to £100.
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