Missing a National Insurance number?

If an employee forgets their National Insurance number (NINO), or needs a letter confirming it, there are options.

They can be advised to:

  • check previous paperwork – payslips, P60, tax, pensions or benefits correspondence
  • Complete the form CA 5403 online available on gov.uk here, printed and posted to HMRC but can take up to 15 days. It is not designed for anyone who has not had a NINO before. A different process applies here
  • phone the National Insurance Number Helpline, 0300 200 3500 – though this only takes requests: HMRC won’t give NINOs over the phone. Information is sent by post, with a 15-day timeframe
  • go online via the personal tax account, or use the HMRC app. Going online is HMRC’s preferred route, and should be the quickest. Employees can be directed here gov.uk/personal-tax-accountto set up a personal tax account. From this, they can share, print or view a copy of their NINO confirmation letter.

Where employees are unable to provide you with a NINO by the time you run your payroll, HMRC suggests that the relevant field on your Full Payment Submission is left blank.