A reference number used by the government is called the National Insurance number. The National Insurance number can be tracked in an official document such as the pay-slip, National insurance card, or letter from the HMRC / Department of work and pensions. Students can track their insurance number in their university registration documents or student loan application.  Almost everyone in the United Kingdom has a National Insurance number. If an individual doesn’t have a National Insurance number, he / she will be required to explain the reason. The Electoral services team will contact and check for the proof of identity.

Lost Your National Insurance Number

Just before the 16th birthday, an individual will receive a National Insurance (NI) number, which appears somewhat like AB123456C.


In situations when the National Insurance number is lost or cannot be found, the HMRC enquiry service can be contacted. Please note that the HMRC will not share the details regarding the National insurance number over the phone, rather the department will share it over a post. A written application can also be sent to the HMRC at:

HM Revenue & Customs (HMRC)
National Insurance Contributions (NIC) & Employer Office National Insurance (NI) Registrations

Benton Park View, Newcastle upon Tyne
NE98 1ZZ

If there is no internet access, the National Insurance Registrations Helpline contact number is 0300-200-3502 (Helpline timings: open from 8 AM to 5 PM, Monday to Friday). The HMRC can also be contacted by completing an online form on the website. Even if a person is doing part-time work or has a low wage to pay NI contributions, still a National insurance number is required to get  a job. An individual will not be permitted to enroll for work at an employment agency with no paper confirmation of NI number. As stated earlier, if an already issued National Insurance number is lost, it can be found on pay-slips, form P60, or tax letters, pensions and benefits. The NI number can also be viewed at the personal tax account. In case the number cannot be tracked, form CA5403 needs to be filled.

Lost national insurance number – To track the number, CA5403 form can be accessed by clicking here.


An individual can apply for a NI number over a phone.

  • National Insurance number application line
    Telephone: 0345 600 0643
    Text-phone: 0345 600 0644
    Day and time: Monday to Friday, 8 AM to 6 PM
  • Welsh language: 0345 602 1491
    Day and time:  Monday to Friday, 8:30 AM to 5 PM

If an individual is moving to the United Kingdom, the National insurance number must be printed on the back of the biometric residence permit (BRP). Re-application is not required if the BRP is already printed. But, in case, an individual does not have a NI number, it is important to apply for one. The application process can only be initiated once the person is in the United Kingdom. A work permit or a study letter in the United Kingdom is a mandate for getting a National insurance number. Individuals can start to work, after proving that the individual is permitted to work in the UK, before the NI number actually arrives. The employer can be informed about the same and the NI number must be submitted once he / she receive it.

Lost national insurance card – National Insurance number interview

An individual might be required to come for an interview, where he / she will be asked by the circumstances and the reason for applying for a NI number. The letter will also include details to the documents needed to prove the identity, example,

  • passport or identification card
  • permit of residence
  • certificate of birth or adoption
  • certificate of civil partnership or marriage
  • driving license

At the interview, the individual will be informed about the duration by with he / she will receive the National Insurance number.

Turning 16 and don’t have a NI number

It’s a normal procedure to automatically receive a National Insurance number before the 16th birthday. If an individual didn’t get one and the age is under 20, he / she must call the National Insurance numbers helpline. For people above 20 years, need to apply for a National Insurance number.


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Other Locations

HMRC Offices

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