Energy giant E.ON is being forced to payback millions of pounds to customers they mistakenly overcharged.
Independent watchdog Ofgem is ordering E.ON to compensate each of the 94,000 customers who were paying too much for their energy bill.
Not only will wronged customers see repayment but E.ON will also pay customers interest so they are not left out of pocket.
As a gesture of goodwill an additional payment of around £300,000 will be made to a fund the energy firm runs in partnership with Age UK.
E.ON will pay around £1.4 million to those where were incorrectly charged exit fees or overcharged following price rises.
Under Ofgem obligations, suppliers have to give customers 30 days notice of a pay rise which allows customers time to switch suppliers before the increase.
If a customer informs their supplier that they wish to move within this time frame no exit fee or higher charges occur, even if the customer switches after the price rise.
“Ofgem has put in place protections for consumers so they can get a fair warning if their supplier puts up prices and time to shop around for a better deal. E.ON has accepted it failed to meet these protections,” said Sarah Harrison, Ofgem's Senior Partner in charge of enforcement.
“Today's announcement that E.ON will compensate customers is a positive step by the company to put right their mistakes and is welcome.”
Ann Robinson, Director of Consumer Policy atuSwitch.com, said: “This announcement is very welcome. Ofgem and E.ON are taking a good and sensible approach which will ensure that customers are not left out of pocket.”