HM Revenue & Customs has issued its own warning about mistakes in the tax codes currently being issued to taxpayers.
Coding notices tell taxpayers how large their personal tax allowance will be in the coming tax year, and how much tax their employers should deduct.
However, earlier this week the Chartered Institute of Taxation warned that many faulty or duplicate notices were being sent out.
Now HMRC has acknowledged that there is a problem.
The HMRC website says the problem is a temporary side-effect of the creation of a database in a new computer system introduced to manage the collection of PAYE and national insurance.
"The transition to the new [computer] system has, however brought to light discrepancies in our existing records and this is resulting in a number of incorrect notices being issued," HMRC said.
"Anyone who is concerned that their code may be wrong should check it using the guidance included with the code and on our website," HMRC said.
