Half a million people and small businesses may not getting compensation from their energy company for poor service or wrong billing, Labour claimed today.
Labour said this means unresolved complaints could be up to 20 times higher than official complaint figures suggest.
It referred to a 2013 report by regulator Ofgem which found 5% of eligible cases are being referred to the Ombudsman.
MP Caroline Flint, the Shadow Energy Secretary used the figures to hammer home her own complaint about suppliers.
She said today: “It’s bad enough when the public have cause for complaint with their energy supplier but for energy companies to refuse to compensate consumers or string out the complaints process for months on end is completely unacceptable.”
However trade body Energy UK rebuffed the criticism of its members as “wilful misrepresentation”.
The outgoing Chief Executive Angela Knight said: “It is wholly unacceptable to confuse genuine problems with people ringing up for explanations they get there and then. Eighty per cent of all queries are dealt on the day with just a single phone call.”
The Ombudsman acknowledged there is an “upward trend” of energy complaints since the start of the year.
Chief Ombudsman, Lewis Shand Smith said: “A total of 4,354 complaints were made… during September 2014…
“With energy prices rising at the end of last year, more and more customers are getting frustrated, proven by the fact that complaints to us have trebled from this time last year.”