National Insurance Number

A National Insurance Number is a personal reference number. It is unique to an individual and stays the same for life. It makes sure that the National Insurance contributions and tax paid are properly recorded against the individual's name. It also acts as a reference number when communicating with the Department of Work and Pensions and HM Revenue & Customs (HMRC).

It is a 9 character reference made up of letters and numbers in the format QQ123456A. It can be found on the National Insurance notification letter, other letters or forms from the Department for Work and Pensions or HMRC or, on payslips if the individual has been employed.