The watchdog reported that, while British Gas has approximately 30% of all gas and electricity accounts in Britain, the company accounts for more than 70% of all complaints. RWE npower was the utility with the next highest level, which, at 2,535 complaints, accounted for 9% of the total complaints recorded by Energywatch.

The watchdog also revealed that, of the British Gas complaints received between October 2006 and March 2007, 15,456 were about billing and 6,600 of those were customers disputing their bills. This led price comparison website to report that British Gas consumers are becoming increasing dissatisfied with the company’s ‘guesstimation’ of quarterly energy bills.

British Gas’ problems are also reported to have been caused by the company’s attempts to implement an electronic billing system by migrating customers’ accounts to a database, uSwitch reported. Although this should reduce complaints in the long-run, problems have increased in the short term.

Geoff Slaughter, energy product manager at uSwitch, commented that, although British Gas had led the way in 2007 price reductions among UK utilities, this may not be enough to appease customers. He said: Why should customers now take British Gas at its word when it has a track record of failing to deliver on its customer service promises?

Adam Scorer, director of campaigns at Energywatch, added: Their inability to deal with customers’ problems is inexcusable – customers should not be left hanging on the phone or having to explain their circumstances to several different advisers.

uSwitch reported that British Gas has responded to its customer crisis by saying that it has employed 800 extra staff to help ease customers’ problems in the future.