What is a National Insurance number?
A National Insurance number is a unique personal number used throughout your life in the UK. It consists of two letters, six numbers, and a final letter. Once assigned, it stays with you permanently and helps the government track your National Insurance contributions and tax records.
HM Revenue and Customs uses your National Insurance number to link your earnings and contributions to your personal record. This record determines your entitlement to certain state benefits, including the State Pension. Employers need it when you start a job, and you will be asked for it when applying for benefits, student loans, or opening certain financial accounts.
Your National Insurance number is not proof of identity on its own. It should not be treated as a form of ID in the way a passport or driving licence would be.
When and how do you get one?
If you were born in the UK and your parent or guardian claimed Child Benefit for you, you will usually receive your National Insurance number automatically. It arrives by post shortly before your sixteenth birthday. You do not need to apply for it.
If you did not receive one automatically, or if you have moved to the UK from abroad and have the right to work, you will need to apply. You can start an application online through GOV.UK. Jobcentre Plus, which is part of the Department for Work and Pensions, may then ask you to attend an interview or provide documents to verify your identity.
The letter you receive confirming your National Insurance number is the official record. National Insurance cards ceased production in 2010, so while some people may still have their old cards, new ones are not issued. Keep your letter somewhere safe. If you lose it, you can find your number through your personal tax account on GOV.UK, on your P60, on your PAYE coding notice, on previous payslips, or on letters about your tax, pension or benefits from HMRC.
Your situation may be slightly different. ask a question below ↓ and our editorial team will reply with our advice.
Why it matters for identity theft
Using someone else's National Insurance number without permission is illegal. If a fraudster obtains yours alongside other personal details, they may attempt to work under your name, claim benefits fraudulently, or use it as part of a wider identity theft scheme.
Because your number is linked to your earnings and tax record, any misuse can create problems that take time to resolve. You might find unexpected employment records appearing on your file, receive tax demands for work you did not do, or discover that someone has claimed benefits in your name.
To reduce the risk of misuse:
- Only share your National Insurance number when required by legitimate authorities or processes, such as your employer, HMRC, or your pension provider.
- Exercise caution with any unsolicited contact requesting your number. HMRC will not contact you out of the blue to ask for it.
- Avoid carrying documents showing your National Insurance number unless necessary.
- Ensure secure disposal of old paperwork containing your National Insurance number by shredding.
- Review your personal financial documents and records regularly for any discrepancies.
What to do if you think your number has been misused
If you suspect someone is using your National Insurance number fraudulently, contact HMRC as soon as possible. They can check your record for any unusual activity and advise on the next steps. You can report the issue through the GOV.UK website or by calling the National Insurance helpline.
You should also check your credit report for any unexpected accounts or applications. The three main credit reference agencies in the UK are Experian, Equifax, and TransUnion. Reviewing your report can help you spot signs that your personal details are being used elsewhere.
If you believe you are a victim of identity fraud more broadly, report it to Action Fraud, the UK's national reporting centre for fraud and cybercrime. They can provide a crime reference number and guidance on protecting yourself further.
Thanks
Brenda
My purse has been stolen containing my NI card. What should I do?
Rosie
My purse has been stolen and my NI card was in it...what do I do
Rosemary
I just found out that my first employer ha using my NI without my permission even after I left job from there.i left job from there in 2015 but on 29 August I received letter saying I owe *** this amount so I have to oy tax but when I look at the statement my old employer paid me salary which is for 5 months.but I stoped working for him in 2015 should I report him to police that he has used my NI without my consent and I wasn’t working there????
I cancelled my cards, reported it to the police and told HMRC.
Should I have told Action Fraud?
Im worried about my National Insurance number falling into the wrong hands.
I am terrified.
Please can you help
.please can you help me
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