Npower, one of Britain’s biggest energy suppliers, has been fined £1.8 million for mis-selling gas and electricity contracts to consumers.

Ofgem, the industry regulator, said Npower had breached the terms of its suppliers’ licence by failing to take swift enough action following complaints from customers about visits from the company’s doorstep salespeople.

Sarah Harrison, Ofgem’s Managing Director of Corporate Affairs, said: “This decision sends a clear message to energy suppliers that failing customers and falling short of the licence standards will lead to Ofgem action, as well as associated reputational damage.

“Mis-selling undermines consumer confidence, but getting it right on the doorstep can help customers make effective choices in the energy market. This is why Ofgem’s energy supply market probe committed to strengthening the doorstep selling rules.”

The censure follows a Sunday Times investigation earlier in the year, which revealed dirty tricks used by Npower sales staff.

Ofgem acknowledge that Npower did have procedures in place to follow up complaints, but decided that company managers had not been proactive in applying them.

It said the fine would have been higher had the company not demonstrated its willingness to deal with a culture of aggressive doorstep selling in which products and charges were sometimes misrepresented by its representatives.

“This allowed incidents of mis-selling to proceed unchecked. As a result Ofgem concluded that npower had failed in its duty to ensure that it had taken all reasonable steps to remedy the matter."

Npower, which is owned by German power giant RWE, has yet to respond to the announcement.

Britain’s Big Six domestic energy providers include N-Power, Centrica, EDF Energy, EON, Scottish & Southern Energy, and Scottish Power.

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