Energy customers 'missing millions'
More than four million customers made complaints to the six major energy suppliers in 2011, according to the report by Which?, with mistakes on bills and inaccurate meter readings causing the most hassle.
But 90% of unsolved complaints are not taken to the energy ombudsman for resolution, meaning that an estimated £4 million in compensation may be going unclaimed.
According to Which?, real levels of customer dissatisfaction are going under the radar because energy companies are not obliged to publish the number of complaints they receive, how long they took to resolve or what the issue was.
Richard Lloyd, Which? executive director, said: "Ofgem, the energy regulator, should publish the truth about the full level of complaints in this essential service.
"Energy suppliers should be held publicly accountable, on a regular basis, for putting right the problems their customers are reporting. It is a sign of the level of frustration with this industry that so many people have a problem but don't complain, even when they could be missing out on compensation."
Customers can take their complaints to the energy ombudsman for free, but only if it remains unsolved after eight weeks or the supplier sends a deadlock letter saying it can do no more. Some 95% of complaints looked at by the ombudsman are upheld and 70% of them receive financial redress.
An annual energy company satisfaction survey carried out by Which? showed that the biggest six energy suppliers - British Gas, EDF Energy, E.ON, Npower, SSE and Scottish Power - were all rated poorly by their customers.
Only 41% of Npower customers said they were satisfied with the company's service or likely to recommend it to others. EDF Energy (43%) and Scottish Power (44%) did not do much better. E.ON and British Gas both received the endorsement of 47% of those surveyed, while SSE was the only "big six" company to satisfy more than half of its customers, with 51%.
© 2012 Press Association