Five free ways to find it
- Paperwork you already have: any payslip, P60, or letter about tax, pensions or benefits — the number (format: two letters, six digits, one letter, e.g. QQ 12 34 56 C) is printed on most of them.
- The free HMRC app — download it, sign in, and view, save or print your number straight away. You can even add it to your phone's wallet.
- Your personal tax account at gov.uk — same thing in a browser.
- Online request form — if you can't use the app or tax account, ask HMRC to post the number to the address they hold for you.
- Form CA5403 or phone 0300 200 3500 — the traditional routes. Either way the confirmation comes by post; HMRC will never read your number out over the phone.
No card needed
HMRC stopped issuing plastic NI cards years ago. The number is all an employer, bank or pension provider ever needs — the app, your tax account or a confirmation letter all prove it.
The NI number scam call
"Your National Insurance number has been compromised" — hang up
Action Fraud has warned about automated calls telling you your NI number has been "compromised", "suspended" or "used in fraud", and to press 1 to fix it. The caller then pressures you into handing over your date of birth, address or banking details to "issue a new number". It is always a scam. Your NI number cannot be suspended and is never reissued by phone. Hang up, report it to Action Fraud (0300 123 2040), and forward scam texts free to 7726.
- Never pay a website to find or apply for an NI number — it's a free government service, and fee-charging sites at the top of search results add nothing but their fee (some also harvest your identity details). Start at gov.uk.
- Share your NI number sparingly — employers, HMRC, DWP, your pension provider and banks have legitimate reasons; random callers never do. With your NI number plus a few other details, fraudsters can attempt identity theft.
- Worried something was a scam? Run it through Sorted's scam checker in seconds.
Never had one? How to apply
- Most people who grew up in the UK get their NI number automatically just before their 16th birthday (if their parent claimed Child Benefit — one more reason claiming it matters even for higher earners).
- If yours never arrived, or you've moved to the UK and have the right to work, apply free at gov.uk/apply-national-insurance-number. You may be asked to prove your identity online or at an appointment.
- You can usually start work before it arrives — you must prove your right to work, and tell your employer the number has been applied for.
Do this now
Download the free HMRC app and sign in — your NI number is there in minutes, plus your tax code, State Pension forecast and National Insurance record (gaps in that record affect your State Pension — worth a look while you're in there).
Got the "compromised" call? Report it to Action Fraud on 0300 123 2040.