A National Insurance number, often abbreviated as NI number, is a unique reference number used by the United Kingdom government to keep track of an individual’s National Insurance contributions. It is used to calculate and pay the correct amount of National Insurance, which is a tax that helps to fund the UK’s welfare system. Everyone who works in the UK, or who receives a state pension or other benefits, needs to have a National Insurance number.
There are many benefits to having a National Insurance number. For example, it allows you to work in the UK, claim benefits, and receive a state pension. It is also used to calculate tax and National Insurance contributions.