A National Insurance number is unique to each individual, and is your “personal” account number. The National Insurance number ensures that all National Insurance Contributions and tax are recorded on your own individual account. This is crucial as National Insurance Contributions can affect future entitlement to some state benefits and pension.

The number is also a reference number for the system used by social security. Every number is different and is comprised of two letters, six numbers with one letter at the end; for example, AA000000A. The National Insurance number will never change, whether you get married, change your name or go abroad to live. You will keep the number for your lifetime as an indication of National Insurance Contributions and tax you have paid.

If you are a resident of the UK, you will usually receive your National Insurance number at the age of 16. The number will be required when you start a new job or apply for a student loan. If you don’t receive a National Insurance number, you can contact the National Insurance Registrations helpline to apply. Prior to issuing a National Insurance number, you will be invited to an interview where you will be asked for documentary evidence of your identity, to prove who you are. You will also be asked to prove evidence that you are entitled to work in the UK, and without this you may be refused a National Insurance number. Temporary National Insurance numbers which start with the prefix ‘TN’ followed by the date of birth and either ‘M’ or ‘F’ for male or female, are no longer valid and shouldn’t be used.

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About The Author

Gary Fields

Content Writer working alongside our expert accountants to bring you the latest Tax and Accounting news.

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