The UK tax authorities have been voted the worst for getting bills wrong in an annual poll.
Consumers believe that HM Revenue and Customs (HMRC) was the worst culprit for sending out inaccurate bills between 2010 and 2011.
Last year, HMRC said that nearly six million people paid too much or too little income tax through the Pay As You Earn (PAYE) system. It wrote to 5.7 million people affected to tell them whether they were due a rebate or had to make more payments.
Energy suppliers have consistently been the worst "billers" since 2007, but this year they were pipped to the post by HMRC, according to the survey conducted by YouGov on behalf of website uSwitch.com.
The questionnaire also found that nearly a third of households have been billed incorrectly by their energy company within the last two years. One in 10 respondents said the blunders happened more than once in the same period.
A spokeswoman for the website said more than 10 million households have unexpectedly ended up owing money to their energy supplier following a discrepancy between an estimated bill and an actual bill. The average amount owed was £147.
Ann Robinson, director of consumer policy at uSwitch.com, said: "Inaccurate bills are no laughing matter for consumers, who can end up out of pocket and wasting time and effort trying to resolve billing blunders.
"The fact is that households are at the blunt end of hugely varying standards in billing accuracy, with some industries, companies and organisations performing noticeably better than others and some consistently coming in at the bottom of the class."
:: The survey was completed by 2,022 people in January.
