If you are new in this country and you are over 16, you need to have your NI number if you are going to work. You pay your National Insurance contributions to build up your entitlement to certain social security benefits, including the State Pension.

The type and level of NIC you pay depends on how much you earn and whether you're employed or self employed. You stop paying NICs when you reach State Pension age.
Who pays National Insurance?

You pay NICs if you are an employee or self-employed and you are aged 16 and over, providing your earnings are more than a certain level. You stop paying NICs at State Retirement age. This is currently 65 for men and 60 for women but will gradually increase to 65 for women over the period 2010 to 2020.

How to get an NI number
If you don't already have a NI number you must apply for one:

• as soon as you start work
• as soon as you or your partner claims benefit

To be able to apply you must be:

• over 16 years of age
• resident in Great Britain (England, Wales or Scotland)

You will have what is called an "Evidence of identity interview", usually one-to-one (unless, for example, you need an interpreter). The interviewer will ask you questions about your background and circumstances.

Find out everything you need to know and apply online here