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Your National Insurance Number


What is my National Insurance number and what is it for?

Only one number is allocated to you and you keep that same number all your life. It is unique to you and ensures we correctly record National Insurance contributions or credits to your National Insurance account. You will need these contributions and credits when you come to claim benefit, whether it is for a short while, like Incapacity Benefit or long term, such as your Retirement Pension.

  • Your National Insurance (National Insurance) Number is personal to you.
  • It is your account number allocated to you for you to use in all your dealings with HMRC and the Department for Work and Pensions (DWP - a new Department comprising in parts the former Department of Social Security).
  • It is not proof of your identity.
  • It looks something like this: AB123456C

This National Insurance number is only an example and should not be used as your own number.

Who else uses my National Insurance number?

Your National Insurance number will also be used by:

  • Employers, for the deduction of tax and National Insurance contributions.
  • Jobcentre Plus, to admiNational Insurancester Jobseeker's Allowance.
  • Local Authorities, to admiNational Insurancester Housing Benefit.
  • HM Customs and Excise to admiNational Insurancester VAT Registration applications

You must not let anyone else use your number.

What do I do with my National Insurance number?

You should quote it on letters or forms you send to HMRC, DWP (formerly DSS) or in Northern Ireland, the Social Security Agency.

Keep your number safe and do not disclose it to anyone who does not need it. Remember, its purpose is only to record National Insurance contributions and credits you have paid or are entitled to; and to help decide how much benefit you are entitled to.

Tell your nearest Social Security office (This is a link to the DWP (formerly DSS) website) or HMRC (National Insurance Contributions) office at once if there is a change in your name, address or title so your National Insurance account can be kept up to date. We may need to contact you if you need to pay more contributions in a particular year to make that year count for pension purposes or when you come to claim benefits like Retirement Pension.

If you are employed.

  • You should tell your employer your number as soon as you know it.
  • Your employer will use it to make sure the contributions you pay are recorded on your National Insurance account. These contributions earn you entitlement to benefit. If your employer does not have the correct National Insurance number then there could be a delay in establishing how much benefit you should get when you claim.

If you are self-employed

  • You will need your National Insurance number when you apply to pay self-employed National Insurance contributions.

When do I apply for a National Insurance number?

No one has a legal right to a National Insurance number but there are circumstances you are legally obliged to formally apply for one and to register for National Insurance purposes.

Criteria for applying for a National Insurance number

  • If you do not already have a National Insurance number you must apply for one as soon as you start work or you or your partner claims benefit.
  • You must be over 16 years old and resident in Great Britain.

If you satisfy all the above conditions except for being resident in GB, and you still want to apply for a number, you must be liable to pay National Insurance contributions or want to pay voluntary contributions and would benefit from doing so.

Providing you satisfy these conditions, you should contact your nearest Social Security office (This is a link to the DWP (formerly DSS) website) and ask for an appointment to be interviewed for a National Insurance number.

At the interview you will need to be able to prove your identity.

You can find out information about the types of documents you should provide to help establish your identity in leaflet GL25 available from any Social Security office (This is a link to the DWP (formerly DSS) website).

What if I have already been given a number but I can't remember what it is?

If you think you already have a number but cannot remember it, see if you can find it on any official papers you may have at home. Look on any of the following:

  • An end of year statement of tax and National Insurance paid - P60 (PDF 92K)
  • Payslip, recent or old.
  • Official correspondence.
  • Annual tax return.
  • Sub contractors tax certificate. (CIS6)
  • Employers wage records.

Your number will not change. Even if for example, you go abroad, marry or change your name your National Insurance number will stay the same.

If you can't find your number, ask at your nearest Social Security office (This is a link to the DSS website) or HMRC (National Insurance Contributions) office and they will tell you what to do.

Will I get a number automatically?

The only people who are automatically registered are those under 16 years old, who live in Great Britain and for whom Child Benefit is in payment. They are automatically registered and a National Insurance number card sent to them just before their 16th birthday.

If these young people do not receive a card they will have to apply for a number in the same way as everyone else (see When do I apply for a National Insurance number). This means they must both be working or claiming benefit and satisfy the criteria shown above.

The National Insurance number card

A plastic National Insurance number card is issued automatically when you first apply for a number or if you change your name on marriage.

It is meant to be a reminder of your number and nothing else. It does not provide proof of your identity and should not be used as such.

If you live abroad a card will not be sent to you. If you live in the United Kingdom but have no permanent address you will be able to collect your card from the Social Security office about 8 weeks after your application is made.

If you live in Wales, you may ask for your card to be printed in both English and Welsh. Tell the office where you apply for your National Insurance number that you would like a bilingual card.

Take good care of your card. You will only be sent one replacement if you lose it.

I've lost my National Insurance number card

Report it to your nearest Social Security office (This is a link to the DSS website) or HMRC (National Insurance Contributions) office. If you want a replacement card you will need to complete an application form. Remember, you are only allowed one replacement.

Do you need to know if I move or change my name?

Yes we do. Please write to your nearest Social Security office (This is a link to the DWP (formerly DSS) website) or HMRC (National Insurance Contributions) office quoting your National Insurance number. Tell us what change has occurred e.g., new address or change of name and when it happened.

If you do not tell us when you move, marry or otherwise change your name we will not be able to keep your records up to date. This means we will be unable to contact you if we need to; for example, if the contributions you paid in a tax year are not enough for that year to count for benefit purposes. We would normally write to let you know and to tell you how much you could pay in voluntary contributions to make that year count.

If you change your name, please return your old National Insurance number card to your nearest Social Security Office when applying for a card in your new name.

Also, when you are nearing the State retirement age, we invite you to claim any Retirement Pension you are entitled to. We cannot do this if we do not have your current address. If you are a woman you should tell us if you get married or become divorced or widowed. All these things may help improve the amount of pension you are entitled to when you come to retire.