National Insurance UK 2026/27 — Rates, Classes, Credits and State Pension

How to Find Your National Insurance Number UK

How to find your National Insurance number. Where to look, how to get a replacement letter, and what to do if you've lost your NI number.

Tax information is based on HMRC rules for the 2026/27 tax year. Tax rules can change — always verify current rates at GOV.UK. This is not tax advice. Consider consulting a qualified tax adviser for your personal situation.

Can’t find your National Insurance number? Here’s how to track it down quickly.

For the wider cluster covering NI rates, credits and employer-cost context, use the main National Insurance hub.

Read more: See our Take Home Pay guide for a complete overview of this topic.

What Your NI Number Looks Like

Format

ComponentExample
Two lettersAB
Six numbers12 34 56
One letter (A, B, C, or D)C
Full formatAB 12 34 56 C

What It’s For

PurposeWhy Needed
TaxHMRC tracks your earnings
National InsuranceContributions recorded
BenefitsClaims processed
PensionsState Pension record
EmploymentEmployer needs it

Where to Find It

Check These First

DocumentWhere to Look
PayslipUsually shown
P60End of year tax summary
P45When you leave a job
Tax returnPrevious submissions
HMRC lettersVarious correspondence
Pension statementsFrom provider
Benefits lettersDWP correspondence

Less Obvious Places

SourceDetails
Old NI cardIf you still have it
Student loanSLC correspondence
ISA paperworkProvider may have
Mortgage applicationYour records
Employment contractSometimes included

Find It Online

Personal Tax Account

StepAction
1Go to gov.uk/personal-tax-account
2Sign in with Government Gateway
3Your NI number is displayed

If You Don’t Have Government Gateway

StepAction
1Go to gov.uk/government-gateway
2Create an account
3Verify your identity
4Access Personal Tax Account

HMRC App

FeatureDetails
DownloadHMRC app (iOS/Android)
Sign inWith Government Gateway
ViewNI number shown in app

Phone HMRC

NI Helpline

DetailsInformation
Number0300 200 3500
HoursMon-Fri 8am-6pm
What they needYour name, address, date of birth
SecurityMay ask security questions

What to Expect

StepProcess
1Automated options
2Security verification
3They confirm your NI number
4May post confirmation letter

Get Written Confirmation

Requesting Confirmation

MethodHow
OnlineThrough Personal Tax Account
PhoneAsk HMRC helpline
PostWrite to HMRC

No More NI Cards

Old SystemNew System
Plastic NI card issuedNo cards since 2011
Many people kept themCheck if you have one
Now useLetters, online account

If You Never Had One

Automatic Issue

WhenHow You Get One
Age 16 (UK resident)Sent automatically
Register for NICIssued if not automatic
Apply for benefitsMay be issued

Applying for NI Number

RequirementDetails
Who needs to applyNon-UK nationals, those not issued automatically
HowCall NI application line
Number0800 141 2075
ProcessInterview and documents

Required Documents

DocumentPurpose
PassportIdentity
BRP (if applicable)Immigration status
Proof of addressTwo items
Evidence of why neededJob offer, etc.

Working Without NI Number

Can You Start Work?

QuestionAnswer
Can employer refuse you?No — can start without it
Will you be paid?Yes
Will you pay correct tax?May be on emergency tax
What to doApply ASAP, employer corrects later

What to Tell Your Employer

InformationProvide
Say“I’ve applied but don’t have it yet”
GiveOther ID (passport, etc.)
TimelineUsually get number within weeks
When you get itProvide immediately

Emergency Tax

What HappensDetails
Without NIMay be taxed at higher rate
When assignedEmployer updates HMRC
Overpaid taxAutomatically refunded
TimescaleUsually sorted within months

Common Questions

“Is my NI number on my birth certificate?”

AnswerDetails
NoNot linked to birth certificate
Issued separatelyAt age 16 or on application

“Can I find it from my NHS number?”

AnswerDetails
NoDifferent systems
NHS numberSeparate identifier
NI numberTax and benefits only

“Can someone else find it for me?”

WhoCan They Help?
EmployerCan’t look it up for you
HMRCOnly tell you directly
FamilyCan’t access your records

“What if someone knows my NI number?”

ConcernReality
Fraud riskSome, but limited
They can’tAccess bank accounts
They couldTry to work under your number
If suspiciousReport to HMRC

Protect Your NI Number

Good Practice

DoDon’t
Keep in safe placeLeave lying around
Memorise itShare unnecessarily
Only give to employer, HMRC, legitimate requestsGive to random websites

Legitimate Requests

OrganisationMay Need It
EmployerYes
HMRCYes
DWPYes
Bank (only sometimes)For specific purposes
Pension providerYes

Summary: Finding Your NI Number

MethodSpeed
Check existing documentsInstant
HMRC app/online accountInstant if logged in
Call HMRC helplineSame day
Request letterFew days
Apply (if never had one)Few weeks

Your NI number is permanent and stays with you for life. Once you find it, note it down somewhere secure so you don’t need to find it again.

You Might Also Find Useful

Sources

  1. HMRC — National Insurance rates and categories
  2. GOV.UK — National Insurance: introduction