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Lost NI number 6 min read Updated 12 Feb 2026

How to find your National Insurance number

The quickest places to check, what to avoid, and when a confirmation letter is the best option.


Your National Insurance number is a personal reference used for tax and National Insurance contributions. If you already have one, you normally do not need to “reapply” — you just need to locate it or request official confirmation.

Where to look first

  • Payslips (often near your name or payroll details)
  • P60 (end-of-year summary from your employer)
  • Letters about tax, benefits, or pensions
  • Your HMRC account (if you have access)

Use the official GOV.UK checklist

GOV.UK: Find your National Insurance number

If you need official proof

If an employer, bank, or another organisation needs official confirmation, a confirmation letter can be the simplest route.

Request a confirmation letter (support)

Plastic NI cards

A plastic NI card can be useful as a personal reminder, but it is not an official government document and is not ID. Only order a card if you already know your NI number.

Order an NI plastic card


Need help with the next step?

We provide independent assistance with HM Land Registry documents and common register update applications. HM Land Registry reviews and decides all applications.

Order Title Register / Plan Deceased Joint Proprietor (DJP) Update the register (AP1) Restrictions & Notices Property Alert

For official information, you can also verify guidance via GOV.UK and HM Land Registry Practice Guides. We are an independent service and not HM Land Registry.