National Insurance numbers: information for employers
When taking on a new employee, one of the details you need to ask them for is their National Insurance number. This is often referred to as a NINO. This page tells you more about National Insurance numbers and what to do if your employee has not got one.
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National Insurance numbers
Every employee must have a National Insurance number. This is used to keep their National Insurance records up to date and ensures their entitlement to various state benefits and the state pension is recorded properly. It also ensures any tax they pay is recorded against the correct name and record on HMRC’s system.
When you take on a new employee, you will need to ask them for their National Insurance number. To ensure the National Insurance number details that the employee gives you are accurate, you should verify the information against an official source such as an old payslip or form P60 from a previous employer. Alternatively, your employee can print you off an official letter confirming their National Insurance number from their Personal Tax Account. They do not need their National Insurance number to access their Personal Tax Account.
National Insurance numbers and checking an employee’s work status
As an employer, you have a responsibility to check that your new employee has a right to work in the UK.
Simply having a National Insurance number should not be relied on by employers as proof that someone has the right to work in the UK. You will need to do your own checks that your employee has the right to work in the UK.
My employee has a temporary National Insurance number
If an employee gives you a National Insurance number beginning with the letters ‘TN’ – this is a temporary (TN) National Insurance number. It may indicate that the employee does not have a proper National Insurance number. TN numbers are not permitted to be used and will not be accepted by HMRC.
A proper National Insurance number is made up of 2 letters, 6 numbers and a final letter, for example AB 12 34 56 C.
The employee will either need to apply for a proper National Insurance number (if they have never had one) or try and retrieve it from HMRC (if they have lost or forgotten it) – we look at both of these options below.
My employee does not have a National Insurance number
If an employee has never had a National Insurance number, for example, because they are a foreign national, they should apply for one.
Please note that your employee can complete a Starter Checklist and start work before their National Insurance number arrives if they can prove they can work in the UK. They should tell you that they have applied for a National Insurance number and give it to you when they have it.
My employee has lost their National Insurance number
If an employee has a National Insurance number (they are usually issued automatically when someone is 15 years and 9 months old) but has lost or forgotten it, they should first check an old payslip, form P60 or any official correspondence from HMRC to see if they can find it.
If they still cannot find their National Insurance number they may be able to obtain it by contacting HMRC and asking them to send a letter of confirmation of their National Insurance number (note HMRC will not tell someone their National Insurance number over the phone) or by logging into their Personal Tax Account (they do not need their National Insurance number to access their Personal Tax Account). HMRC say that the quickest way to get it is using this online route.
Please note that your employee can complete a Starter Checklist and start work before their National Insurance number arrives from HMRC, provided they can prove they can work in the UK.
If the employee still cannot find their National Insurance number, you (as their employer) may be able to obtain it from HMRC. How you do that depends on whether you send information to HMRC online (online filing) or on paper (paper filing).
- Lost National Insurance number – Online filing
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Until February 2025 it was possible to make a National Insurance Number Verification Request (NVR) via payroll software or by using HMRC's Basic PAYE Tools to try to find out an employee’s national insurance number. However, following a review, HMRC has said it has withdrawn the NVR service from 3 February 2025 until further notice. It is not known if or when the service will restart.
When you could submit a National Insurance Number Verification Request, you had to leave the National Insurance number field blank for that employee and HMRC would try to match the employee's details to their National Insurance number. If they were able to do this, they would confirm the number to you and the employee in writing.
If they could not trace it automatically, HMRC could write to your employee and ask them to complete and return form CA5403 – Your National Insurance number, so that they could do a clerical trace.
- Lost National Insurance number – Paper filing
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If HMRC have agreed you can use paper filing, you should follow these steps:
- When you send your new employee's information to HMRC on form RT2, leave the National Insurance number section blank and HMRC will try and trace the National Insurance number and tell you what it is.
- If they cannot trace it automatically, HMRC may have to write to your employee and ask them to complete and return form CA5403 – Your National Insurance number, so that they can do a clerical trace.
