Your National Insurance Number is your unique reference number which records the amount of National Insurance (NI) payments you have made. It is a combination of letters and numbers and it stays the same throughout your entire life.

It is absolutely crucial that your NI payments are correctly assigned to you. Essentially these pay for your State Pension and some other state benefits. Most UK nationals are issued with their National Insurance number on their 16th birthday. Everyone else should apply for their NI number before they start working. You have to have made the correct number of years’ contributions in order to qualify for a full state pension.

I don’t know my National Insurance number, what should I do?

In the olden days, everyone was sent a credit card sized, NI card with their number printed on it; maybe yours is in your files? If not, you can find your NI number on lots of your financial records such as: payslips, correspondence concerning pensions, benefits or tax, and P60s. You can also see it in your digital Personal Tax Account. Get in touch with HMRC if you still cannot find your NI number after a thorough search.

Why do I need to know my NI number?

You need to check that your NI contributions are being properly recorded against your name. You also need your NI number if you are in communication with any of the following agencies:

Security Alert

Your NI number is a totally unique part of your financial identity. Real NI numbers are very useful to criminals involved in identity theft. You must keep your number private and only share or confirm it to authentic organisations. Don’t keep it somewhere obviously labelled in your home or on your person.

To find out more information about your National Insurance number, check out our National Insurance Guide. It includes sections on how much National Insurance you should pay, who pays it and how your employment status affects you National Insurance payments.