Keeping track of your National Insurance number

Keeping track of your National Insurance number is more important than many people realise. Although it may seem like just another reference number, it plays a central role in your tax affairs, employment record and future entitlement to certain state benefits.

Your National Insurance number is used by HM Revenue & Customs and the Department for Work and Pensions to record your National Insurance contributions and tax payments. It is also linked to your State Pension record and can affect your entitlement to benefits such as maternity allowance, contribution-based benefits and the State Pension itself.

Many people only become aware of the importance of their National Insurance number when they start a new job, complete a Self-Assessment tax return or apply for benefits. At that point, not being able to locate the number can create delays and unnecessary stress.

Business owners and employers should also encourage staff to keep their details safe and accessible. Payroll reporting under RTI depends on accurate employee information, including the correct National Insurance number. Errors can sometimes lead to contribution records not being allocated correctly.

It is sensible to keep a secure note of your National Insurance number alongside other important personal records, rather than relying on old payslips or letters to find it later. You may also wish to check that your National Insurance contribution record is complete, particularly if you have had periods of self-employment, part-time work or time spent abroad.