What is a national insurance number?
Your national Insurance (NI) number is unique to you throughout your life but it is not a form of identity. It is made up of 2 letters, 6 numbers and a final letter for example ZY 98 76 54 A.
Everyone who wants to work in the UK must have a national insurance number. To obtain a national insurance number, you must be 16 or over and resident in Great Britain or Northern Ireland.
You can start work without one but you must then apply immediately. The law requires you to apply for NI number if you do not already have one and you are working or are intending to work.