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How to Find Your National Insurance Number

Updated: Jun 23

Understanding the Importance of a National Insurance Number

What is a National Insurance Number?

In the United Kingdom, a National Insurance Number (NIN) is a unique identifier assigned to individuals to track their contributions to the National Insurance system. This number is crucial for various aspects of life in the UK, such as employment, taxation, and access to social services. A National Insurance Number is a 9-digit alphanumeric code that starts with two letters, followed by six numbers, and ends with one letter (e.g., AB123456C).

How to Find Your National Insurance Number  in the UK

The Challenges of Losing Your National Insurance Number in the UK

Financial Implications

Losing your National Insurance Number (NIN) can have immediate financial repercussions. Your NIN is essential for tax purposes, and without it, you could face delays in the processing of your income tax returns. This could result in late fees or even legal issues if not resolved promptly. Moreover, your employer needs your NIN to correctly calculate your tax contributions. A missing NIN can disrupt this process, potentially affecting your take-home pay.

Employment Hurdles

When you start a new job, your employer will ask for your NIN to set up your employment records and manage your tax contributions. Without a NIN, this process becomes complicated. Some employers may even hesitate to finalize your employment until you provide a valid NIN, which could lead to delays in starting your job or even loss of employment opportunities.

Access to Benefits and Services

Your NIN is crucial for accessing various social security benefits, including unemployment benefits, child benefits, and state pensions. Losing your NIN can make it difficult to claim these benefits, requiring you to go through a cumbersome process to prove your eligibility. This can be particularly challenging for those who are already in a vulnerable financial situation.

Healthcare Access

In some instances, you may be asked to provide your NIN when accessing certain healthcare services. While the NHS does not strictly require a NIN, having one can streamline the administrative process. Without it, you may face delays or additional paperwork, complicating an already stressful situation if you're in need of medical care.

Rental and Housing

Landlords and rental agencies often ask for a NIN as part of their background checks. A missing NIN can slow down this process and create unnecessary complications. In a worst-case scenario, a landlord may choose another tenant who can provide all the required information promptly.

Banking and Financial Transactions

While not a standard requirement, some financial institutions may ask for your NIN during the account opening process or for certain transactions. Without it, you may face delays or additional scrutiny, which can be both time-consuming and frustrating.

Identity Theft Risks

Losing your NIN isn't just about the number itself but also the risk of it falling into the wrong hands. Your NIN, combined with other personal information, can be used for identity theft. Fraudsters can use it to open bank accounts, secure loans, or commit other forms of financial fraud in your name, which can have long-lasting implications for your financial health.

Emotional and Psychological Strain

The stress and anxiety associated with losing such an important piece of identification should not be underestimated. The process of recovering or replacing a lost NIN can be bureaucratic and time-consuming, adding emotional strain to the practical difficulties you're already facing.

Legal Consequences

Failure to provide a NIN when legally required to do so can result in fines or other legal penalties. While these are generally a last resort, the risk increases the longer you go without resolving the issue of your missing NIN.

In summary, losing your National Insurance Number in the UK can create a domino effect of challenges, affecting various aspects of your life from employment and finances to access to social benefits and healthcare. The sooner you take steps to recover or replace your lost NIN, the less impact these challenges will have on your life.

Why is it Important?

Having a National Insurance Number is essential for several reasons:

Employment: Employers require your NIN to record your tax contributions.

Taxation: The HM Revenue and Customs (HMRC) uses your NIN to identify you within the tax system.

Social Benefits: Access to social services like healthcare and unemployment benefits are tied to your NIN.

Pensions: Your pension contributions are also recorded against your NIN.

National Insurance contributions count towards the following benefits and pensions:

​Benefits and Contributions

Class 1: Employees

​Class 2: Self-Employed

​Class 3: Voluntary Contributions

​Basic State Pension




​Additional State Pension




​New State Pension




​New Style Jobseeker’s Allowance




​Contribution-based Employment and Support Allowance




​Maternity Allowance




​Bereavement Support Payment




How Do You Usually Get It?

When you turn 16, you automatically receive a National Insurance Number from the Department for Work and Pensions (DWP). You'll typically receive a letter containing your NIN, and it's advisable to keep this document safe. Additionally, your NIN can appear on your bank statement if your pension is paid into your bank account.

What if You Lose It?

Losing your National Insurance Number (NIN) can feel stressful, but there's no need to panic. The first thing to remember is that a lost NIN doesn't mean your personal information is immediately at risk. The number alone isn't enough for identity theft. You can easily retrieve your NIN by contacting the HM Revenue and Customs (HMRC) or by checking official documents like your tax return or payslips. If you're still concerned, you can also take additional security measures like monitoring your accounts for unusual activity. So, take a deep breath; you've got options to set things right like:

HMRC Helpline: You can contact the National Insurance Numbers helpline of HMRC.

Online Services: The UK government offers online services where you can find your lost NIN.

Confirmation Letter: You can request a confirmation letter to be sent to your home address.

Bank Statements: If your pension is paid into your bank account, your NIN might be listed there.

How to Use Official Resources to Find Your NIN

The UK government provides several resources to help you find your lost National Insurance Number: This is the official website where you can find comprehensive information about retrieving your lost NIN.

East Cambs: This local government website also provides valuable information on how to find your NIN.

NI Direct: This is another useful resource for residents of Northern Ireland.

TV Licensing: Interestingly, the TV Licensing website mentions that your NIN can be found on your bank statement if your pension is paid there.

Understanding the importance of a National Insurance Number and knowing how to retrieve it if lost are crucial for anyone living in the UK. In the next part, we will delve deeper into the step-by-step process of finding your lost National Insurance Number, including the documents you'll need and the procedures to follow.

Step-by-Step Guide to Finding Your Lost National Insurance Number

Utilizing Online Services

One of the most convenient ways to retrieve your lost National Insurance Number is through online services. The UK government offers a Personal Tax Account where you can view, download, print, save, or share a letter containing your NIN. If you haven't registered for a personal tax account yet, you can easily do so online. Once registered, you can log in to your account to find your NIN.

Filling in the Online Form

If you're unable to register for a personal tax account, there's an alternative. You can fill in an online form provided by the government and post it. This method is a bit more time-consuming but equally effective. After submitting the form, you'll receive a letter confirming your National Insurance Number.

Contacting HMRC Helpline

If you're between the ages of 15 years and 9 months and 20 years old and haven't received your NIN, or if you're over 20 and still don't have one, you can call the HMRC helpline for advice. If you have lost your NIN, HMRC won't disclose your National Insurance number via phone. Instead, they will mail it to you, and you can expect to receive it within a span of 15 working days. The helpline numbers are as follows:

Within the UK: 0300 200 3500

Textphone: 0300 200 3519

Outside the UK: +44 191 203 7010

The helpline is open from Monday to Friday, 8 am to 6 pm, and is closed on Saturdays, Sundays, and bank holidays.

Using Official Documents

Your National Insurance Number can also be found on various official documents:

Payslip: Check your most recent payslip from your employer.

P60: This is your end-of-year tax summary provided by your employer.

Tax Returns: If you've filed a tax return, your NIN would be listed there.

Official Letters: Any official correspondence about tax, pensions, or benefits will likely contain your NIN.

Reporting Scams

Be cautious of scams related to National Insurance Numbers. If you receive a suspicious phone call, email, or text that you believe is a scam, you can report it to HMRC. This is crucial for protecting your personal information and preventing identity theft.

Using the HMRC App

HMRC also offers an official app where you can find information about your National Insurance Number. This is a convenient option for those who prefer using mobile applications for such tasks.

You can download the app from:

What is HMRC Form CA5403 and How to Use It to Find Your Lost National Insurance Number?

What is HMRC Form CA5403 and How to Use It to Find Your Lost National Insurance Number?

Losing your National Insurance Number (NIN) can be a stressful experience, especially when you need it for important tasks like employment or tax filing. Fortunately, the UK government provides several ways to recover your lost NIN, one of which is using the HMRC Form CA5403. This form serves as a lifeline for those who have misplaced their NIN and need a written confirmation. In this article, we'll delve into what HMRC Form CA5403 is, how to complete it, and other alternatives for retrieving your NIN.

What is HMRC Form CA5403?

HMRC Form CA5403 is a document provided by Her Majesty's Revenue and Customs (HMRC) to help UK citizens recover their lost or forgotten National Insurance Number. The form is designed to be filled out online, printed, and then posted to HMRC. It's important to note that this form is not for individuals who have never had a NIN before; a different process applies for them.

Who Can Use It?

The form is specifically designed for individuals who have had a National Insurance Number but have lost or forgotten it. If you've never had a NIN, you should not use this form. Instead, you should contact the National Insurance Registrations Helpline or Jobcentre Plus, depending on your citizenship status.

What Information is Required?

The form requires you to answer all questions except those marked 'optional.' Once completed, you can print a copy and post it to HMRC. The form itself is straightforward and asks for basic information to confirm your identity.

How to Complete the Form

Completing HMRC Form CA5403 is a simple process. Here's a step-by-step guide:

Access the Form: Visit the official HMRC website and navigate to the CA5403 form.

Fill in the Details: Complete all the required fields. Make sure the information is accurate to avoid any delays.

Print the Form: After filling it out, print a copy. The form cannot be saved online.

Post to HMRC: Mail the printed form to the HMRC address provided on the form.

You might be required to mail a maximum of two documents from the list below:

  1. Birth certificate

  2. Passport

  3. Full or provisional driving license

  4. Adoption certificate

  5. Home Office or travel documentation

  6. Employment authorization

  7. Naturalization certificate

  8. Marriage or civil partnership certificate

  9. Service certificate from His Majesty's Forces or the merchant navy

  10. Identification or medical card

After submitting your form, expect to receive your National Insurance number via mail within a 15-day timeframe.

Mail the printed and completed form to the following address:

National Insurance Contributions and Employers Office

HM Revenue and Customs


Wait for Confirmation: It can take up to 15 working days for the confirmation letter to be received through the post.

Important Points to Note

The form is not designed to prove your identity; it's solely for confirming your NIN.

If you're unable to provide the NIN by the time your employer runs payroll, HMRC suggests leaving the relevant field blank on your Full Payment Submission.

Alternatives to Using Form CA5403

While the CA5403 form is a reliable method for retrieving your NIN, it's not the only option. Here are some alternatives:

Personal Tax Account: You can view and print a confirmation letter straight away from your personal tax account.

National Insurance Registrations Helpline: You can call the helpline at 0300 200 3500 for assistance.

Check Previous Paperwork: Your NIN may be available on payslips, P60, or other HMRC and DWP letters.

Losing your National Insurance Number is not the end of the world, thanks to options like the HMRC Form CA5403. By understanding how to use this form and the alternatives available, you can quickly and efficiently recover your NIN. So, the next time you find yourself in a bind, remember that help is just a form away.

20 Most Important Places Where You May Find Your National Insurance Number in the UK

National Insurance Card

Your National Insurance (NI) number may be found on your National Insurance card. This card is typically issued when you first receive your NI number. Although physical NI cards are less common now, you might still have one if you received your NI number some years ago.

Welcome Letter or Email from HMRC

When you are allocated a National Insurance number for the first time, HM Revenue & Customs (HMRC) sends a welcome letter or email that includes your NI number. This correspondence is one of the primary documents where you can find your NI number.


Your payslip is a reliable source for finding your National Insurance number, as employers are required to include it on all payslips. This helps in tax and National Insurance contribution calculations.


The P60 is a statement issued to taxpayers at the end of each tax year, detailing their taxable income and deductions, including National Insurance contributions. Your NI number will be prominently displayed on this document.


When you leave a job, your employer will provide you with a P45 form. This form contains details about your earnings and the taxes you've paid during the employment period, including your National Insurance number.

HMRC Correspondence

Any official correspondence from HMRC, such as tax notifications or statements, will likely include your National Insurance number. This includes both digital and paper communications.

Personal Tax Account

By setting up a Personal Tax Account online through the HMRC website, you can view your National Insurance number as well as manage other aspects of your taxes and benefits.

Benefits Correspondence

If you receive state benefits, such as unemployment benefits or a pension, any correspondence regarding these benefits will include your National Insurance number.

Student Loan Documentation

If you have taken out a student loan, your National Insurance number will be used as part of your identity verification and will appear on related documentation.

Bank Statements for Direct Tax Payments

If you make direct contributions to tax schemes or benefits that involve HMRC, these transactions may include your NI number on the bank statements.

Job Centre Plus Documentation

When registering with Job Centre Plus for job-seeking assistance or benefit claims, your National Insurance number will be used and can be found on any related documentation.

Online Payroll Services

If your employer uses online payroll services or HR systems, you can often access your employment details, including your National Insurance number, through these platforms.

Tax Return Forms

Whether you're filing taxes online or on paper, your National Insurance number is a critical part of your tax return forms.

National Insurance Numbercard Letter

If you've ever requested a confirmation of your National Insurance number or a replacement card, the letter you receive in response will have your NI number.

Universal Credit Documentation

Documents and correspondence regarding Universal Credit will contain your National Insurance number, as it is tied to your eligibility for such benefits.

Healthcare Documents

While not common, some healthcare-related documents might list your National Insurance number, especially if they pertain to employment injury or disability assessments related to work.

Mortgage Applications

During the mortgage application process, your lender may keep records that include your National Insurance number as part of your financial profile.

Rental Agreements

Some rental agreements may require your National Insurance number to verify your identity or for background checks, though this is less common.

Driving License Application

In the UK, your driving license application may include your National Insurance number to check your identity against other government records.

Council Documents

Local council documents, such as those pertaining to council tax or housing benefits, may include your National Insurance number for identification and processing of applications.

Each of these documents and places offer a potential avenue for locating your National Insurance number, which is essential for employment, taxation, and accessing government services in the UK.

How to Find Your National Insurance Number in the UK: Additional Insights

The Importance of Safeguarding Your NI Number

Your National Insurance (NI) number is a critical piece of identification in the UK. It's not just a string of characters but a key to your financial and social benefits. Given its importance, it's crucial to safeguard this number like you would your passport or driver's license. Store it in a secure place, and don't share it recklessly. If you're storing it digitally, make sure it's in a password-protected folder or secure cloud storage. The more securely you store it, the less likely you are to lose it and go through the hassle of retrieval.

The Role of Employers in NI Number Retrieval

If you're currently employed or have been in the recent past, your employer can be a valuable resource in finding your lost NI number. Employers usually keep records of their employees' NI numbers for tax purposes. You can request this information from your HR department, and they should be able to provide it to you. This method is often quicker than going through official channels and can save you a lot of time.

Utilizing Financial Documents

Your NI number is often quoted in various financial documents. If you have a pension plan, your NI number will likely be on the paperwork. Similarly, if you have ever taken out a loan or mortgage in the UK, these documents will also typically contain your NI number. Scour through your financial papers, and you might find your NI number listed there.

The Role of Educational Institutions

If you're a student or have recently completed your studies in the UK, your educational institution might have your NI number. Universities and colleges often collect this information for various administrative purposes. Check with your institution's administrative office to see if they can help you retrieve your NI number.

Using the Freedom of Information Act

The Freedom of Information Act allows you to request various types of information from public authorities. While it's a long shot, you could technically file a Freedom of Information request to obtain your NI number. However, this is generally not recommended as your first or even second option due to the time it takes and the complexity involved.

The Role of Family Members

Believe it or not, family members can sometimes come to the rescue when you've lost your NI number. Parents or guardians who are meticulous record-keepers may have kept a copy of your NI number. It's worth asking them if they have any old documents that might contain this valuable piece of information.

The Last Resort: Legal Assistance

If all else fails and you've exhausted all other avenues, you might consider seeking legal advice. Some law firms specialize in identity and document retrieval services. They can guide you through the bureaucratic maze and help you get your NI number back. However, this should be your last resort due to the potential costs involved.

National Insurance Number: How to Get Additional Support from HMRC

Why Your National Insurance Number Matters

In the UK, your National Insurance Number (NIN) is a unique code that helps track your contributions to the National Insurance system. It's essential for employment, taxation, social benefits, and pensions. Your NIN is a 9-digit alphanumeric code, like AB123456C, and it's crucial to keep it safe.

Extra Support You Can Get

If you face challenges when dealing with HM Revenue and Customs (HMRC), they offer extra support tailored to your needs. This could be if you:

  • Have learning difficulties like dyslexia or autism

  • Face physical or sensory disabilities

  • Struggle with mental health issues like depression or anxiety

  • Are going through financial hardship or domestic abuse

  • Are currently in hospital treatment

To access this support, you can schedule a phone or video appointment with HMRC's extra support team. You can request this when you call any HMRC helpline or use their webchat service.

How to Get Support from HMRC

If you're facing challenges when dealing with HM Revenue and Customs (HMRC), don't worry; there's help available. Here's how HMRC can assist you:

Extra Support for Special Circumstances

If you have health conditions or personal circumstances that make it challenging to interact with HMRC, you can get extra support. This includes conditions like dyslexia, autism, physical disabilities, and even financial hardship. Contact HMRC for a phone or video appointment with their extra support team.

Alternative Contact Methods

If you can't use a telephone, there are other ways to reach HMRC. These include text services like Relay UK, webchat, and even British Sign Language (BSL) video interpreters from the InterpretersLive! service.

  • Text Service (Relay UK): Dial 18001 followed by the relevant contact number, like 0300 200 3300 for 'Income Tax: general enquiries'.

  • Webchat: Use HMRC’s extra support team webchat.

  • BSL Video Interpreter: If you use British Sign Language, you can use the InterpretersLive! service.

  • Home Visits: You can also request a face-to-face meeting or home visit by filling out an appointment form.

Need Information in Different Formats?

HMRC provides information in accessible formats for those who need it. This includes:

  • Braille

  • Large print

  • Audio on CD

  • Text on CD

  • Other formats like colored paper

To get these, call the relevant HMRC contact number and specify your needs.

Help with Filling Forms

If you find filling out forms challenging, HMRC can assist you. Just call the relevant contact number and you'll be transferred to HMRC’s extra support team. You can also use their webchat service.

Accessible Information Formats

HMRC provides information in accessible formats like Braille, large print, and audio CDs. If you need these, just call HMRC and they'll sort it out for you.

Extensions and Extra Time

In some cases, HMRC can give you more time to meet deadlines or spend extra time with you on the phone. This is especially helpful if you're facing financial difficulties or health issues.

Language and Interpretation Services

If English isn't your first language, you can use a friend or family member as an interpreter when you call HMRC. They also offer their own interpretation services.

Appointing a Representative

If you find it hard to deal with HMRC yourself, you can appoint someone to talk to HMRC on your behalf. This can be a friend, relative, or an adviser from a voluntary organization.

By exploring these additional avenues, you increase your chances of quickly and efficiently retrieving your lost or misplaced National Insurance number. Remember, the NI number is not just another ID; it's a gateway to various social and financial benefits in the UK. So, treat it with the importance it deserves.

Frequently Asked Questions and Additional Tips for Keeping Your NIN Secure

Frequently Asked Questions and Additional Tips for Keeping Your NIN Secure

1. How can I verify if my National Insurance Number has been compromised?

Regularly monitor your financial accounts and official documents for any unusual activity. If you suspect misuse, contact HMRC immediately.

2. Can I change my National Insurance Number if it has been stolen?

Changing your National Insurance Number is not straightforward and usually only occurs in extreme cases, such as identity theft. You will need to provide evidence and go through a formal process with HMRC.

3. What should I do if I haven’t received my National Insurance Number by age 16?

Contact the National Insurance Registrations Helpline or Jobcentre Plus to inquire about your National Insurance Number status.

4. Are there any online security measures I should take to protect my National Insurance Number?

Store your National Insurance Number in secure, encrypted digital storage and avoid sharing it on unsecured websites or social media.

5. How can I retrieve my National Insurance Number if I’m outside the UK?

You can contact the HMRC helpline from abroad or access your personal tax account online to retrieve your National Insurance Number.

6. Is my National Insurance Number required for opening a bank account in the UK?

Some financial institutions may request your National Insurance Number for verification purposes, though it is not always mandatory.

7. What is the process for obtaining a National Insurance Number if I’m an international student in the UK?

International students should apply for a National Insurance Number through Jobcentre Plus, providing necessary documentation such as passport and visa.

8. Can I find my National Insurance Number on my tax return?

Yes, your National Insurance Number is typically listed on your tax return documents.

9. What should I do if I receive a suspicious email asking for my National Insurance Number?

Report the suspicious email to HMRC and do not provide any personal information. HMRC will guide you on the next steps to ensure your information is secure.

10. How long does it take to receive a National Insurance Number confirmation letter from HMRC?

It generally takes up to 15 working days to receive a confirmation letter from HMRC once you have requested it.

11. What should I do if my employer refuses to finalize my employment without my National Insurance Number?

Explain the situation to your employer and provide evidence that you are in the process of retrieving your National Insurance Number. Contact HMRC for additional support if needed.

12. Can I still access healthcare services without my National Insurance Number?

While having a National Insurance Number can streamline administrative processes, it is not strictly required for accessing NHS services.

13. What happens if I provide an incorrect National Insurance Number to my employer?

Inform your employer as soon as possible and provide the correct number to avoid any issues with your tax and National Insurance contributions.

14. Are there penalties for failing to provide my National Insurance Number when required?

Yes, failing to provide your National Insurance Number when legally required can result in fines or other legal penalties.

15. Can my National Insurance Number be used for identity verification purposes?

Yes, your National Insurance Number can be used for identity verification in various administrative processes, so it is crucial to keep it secure.

16. What should I do if I lose my National Insurance Number multiple times?

Ensure you store it securely, both digitally and physically. Consider using a password manager for digital storage and a locked file for physical copies.

17. How can I obtain a replacement card or document for my National Insurance Number?

Contact HMRC to request a replacement document if your original has been lost or damaged.

18. What are the consequences of using someone else's National Insurance Number?

Using another person's National Insurance Number is illegal and can lead to severe penalties, including fines and imprisonment.

19. How can I report suspected fraud involving my National Insurance Number?

Report any suspected fraud involving your National Insurance Number to HMRC immediately and follow their guidance on how to secure your personal information.

20. Is there any way to expedite the process of retrieving my National Insurance Number?

Using online services such as your personal tax account can expedite the retrieval process. Additionally, contacting HMRC via their helpline may provide quicker assistance.

Q21: Can I Find My National Insurance Number on My Bank Statement?

A: Yes, your National Insurance Number can be found on your bank statement if your pension is paid into your bank account. This is a quick way to locate your NIN if you've misplaced it.

Q22: What Role Does the Department for Work and Pensions (DWP) Play in NIN?

A: The DWP is responsible for issuing National Insurance Numbers. When you turn 16, you should receive a letter from the DWP containing your NIN. Keep this letter in a safe place as it's your official confirmation.

Q23: Can I Use My NIN for Free TV Licensing?

A: Interestingly, your National Insurance Number is sometimes required for specific services like free TV licensing for those aged 74 and over. So, it's not just for tax and employment; it has other utilities as well.

Q24: What Should I Do If I Suspect My NIN Is Being Misused?

A: If you suspect that your National Insurance Number is being misused, it's crucial to report it to the authorities immediately. Contact the HMRC helpline and follow their guidance to ensure your personal information is secure.

Q25: Is There an HMRC App for Managing My NIN?

A: Yes, HMRC offers an official app where you can manage various tax-related tasks, including finding your National Insurance Number. It's a convenient option for those who prefer mobile applications.

Q26: What Are the Helpline Hours for NIN Inquiries?

A: The HMRC helpline for National Insurance Number inquiries is open from Monday to Friday, 8 am to 6 pm. It's closed on Saturdays, Sundays, and bank holidays.

Q27: Can I Find My NIN on Official Documents Like a Payslip?

A: Absolutely, your NIN is often listed on official documents like your payslip, P60, and any correspondence from the HMRC related to tax, pensions, or benefits.



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