Guides › Public Services › Lost Your National Insurance Number? How to Find It
Lost Your National Insurance Number? How to Find It
You can usually find your National Insurance number on a payslip, a P60 or letters about tax, pensions or benefits, or in the HMRC app or your personal tax account, where you can also download a letter showing it. HMRC cannot give you your number over the phone or by webchat; use the GOV.UK tool that shows where to look or how to ask. If you have never had one, you may need to apply.
At A Glance
Your Rights
What the rules say, with a link to the official source for each.
Finding Your Number
Where to Look
A payslip, P60, or letters about tax, pensions or benefits; the HMRC app; your personal tax account; or Apple or Google Wallet if you saved it there. You can download a letter showing your number from the app or your account. source
Asking HMRC
HMRC cannot give you your number over the phone or on webchat. Use the GOV.UK tool to check where to look or how to ask for it. source
Never Had One
You may need to apply, for example if you moved to the UK and have not worked or claimed benefits here. source
Time Limits to Know
Miss a deadline and you can lose a right. Check the dates on your own paperwork.
- Any timeDownload a letterFrom the HMRC app or your account
Steps to Take
Step 1 of 5
Check old payslips, P60s and HMRC letters.
Step 2 of 5
Open the HMRC app or your personal tax account.
Step 3 of 5
Download the letter showing your number.
Step 4 of 5
Use the GOV.UK tool if you still cannot find it.
Step 5 of 5
Be wary of sites charging to find it: it is free.
(Tap the numbers to reveal steps)
Where to Go If It Is Not Put Right
Your options, in order, and when each one applies.
Your Personal Tax Account
Sign in on GOV.UK to check your tax code, income and letters.
HMRC
Contact HMRC through your personal tax account, the HMRC app or the phone and post details on GOV.UK.
Good to Know
Small things that make your complaint stronger.
Finding your number is free. Do not pay a website to do it for you.
Want Help?
If you would like one of our team to look at your problem, our initial case review is free. We cannot guarantee any outcome and we do not give legal advice.
Lead reviewer
Luke Marley
Founder and Lead Reviewer
Luke founded CPUK in 2026 after seeing how hard it is for ordinary people to get problems with companies put right. He oversees our guides and checks them against official sources.
Research by Katie Burt, Co-founder and Operations Lead (17 years in the care sector, including managing services for vulnerable adults), and the CPUK Research Team. Researched with AI-assisted research tools, then checked and corrected by our team.
Last checked: 16 October 2026. We are not paid by the companies we write about. Adverts never affect our guidance. Read our editorial policy.
Sources and official links
- gov.uk/lost-national-insurance-number Checked 16 October 2026