Your National Insurance number is unique to you, and you keep the same one all your life.
What is a National Insurance number?
Your National Insurance number is unique to you, and you keep the same one all your life. It ensures the National Insurance contributions and Income Tax you pay are properly recorded against your name. It also acts as a reference number when communicating with the Department for Work and Pensions (DWP) and HM Revenue and Customs (HMRC).
UK citizens who have always lived in the UK should automatically get a National Insurance number just before their 16th birthday.
How do I apply for one, if I don't already have one?
The easiest way to apply for a National Insurance number (NINO) is online. Go to the gov.uk website, read and click through the information, and then press the green 'apply' button at the bottom of the page.