National Insurance is your contribution to certain state benefits, including the State Pension. How much you pay will affect your entitlement to these benefits.
As an employee, or if you’re self-employed, you’ll pay National Insurance if your earnings are above a certain level. Your employer will also pay National Insurance contributions on your earnings.
You’ll have a National Insurance number that’s unique to you. You will have received this in a letter from HMRC when you were 16.
Find out more about National Insurance numbers.