To ask the Chancellor of the Exchequer what procedures are in place to ensure that letters notifying clients of the cessation of tax credits are not sent in error; and how many such letters have been sent in error since the system was established. (145209)

Procedural guidance for HM Revenue and Customs staff dealing with tax credits can be found at:

http://www.hmrc.gov.uk/manuals/ntcmanual/index.htm

Information about the number of letters is not available in the format requested.