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United Kingdom

The United Kingdom mainly uses the National Insurance Number (NINO) for individuals, the Company Registration Number (CRN) or other 8-character public register number used as the company number for incorporated entities and some society records, the 10-digit Unique Taxpayer Reference (UTR) for taxpayers registered in HMRC regimes such as Self Assessment, partnerships and trusts, and an HMRC charities reference for charities that need an HMRC charity identifier and do not have a CRN.

GB GBR 4 TIN types Last reviewed 2026-05-14

TIN types

4 published formats. Open a type to see examples, structure details, and official sources.

Validate United Kingdom TIN
UK National Insurance Number (NINO)
Current Individuals

HM Revenue & Customs (HMRC) / Department for Work and Pensions (DWP)

Personal identifier used so an individual's tax and National Insurance records are kept against that person.

Details
Examples
AA 12 34 56 A
Where to find it

On payslips, P60s, letters about tax or benefits, and in the personal tax account or HMRC app.

Common names
NINO National Insurance number
Structure
1-2 Prefix Two-letter prefix assigned from a valid NINO series.
3-8 Serial Six-digit serial number.
9 Suffix Historic final letter retained as part of the identifier.
Official source
gov.uk oecd.org
UK Company Registration Number (CRN)
Current Entities

Companies House / Financial Conduct Authority (for certain society records shown on the public register)

Public registration number shown on the UK public register and normally used as the TIN for UK resident companies and LLPs in HMRC DAC7 guidance.

Details
Examples
00123456 SC123456 NC000001 IP01824R CE021135 OE002241
Where to find it

On the certificate of incorporation or registration, in correspondence from Companies House, and on the public register.

Common names
CRN Company number Companies House number
Official source
gov.uk find-and-update.company-information.service.gov.uk ewf.companieshouse.gov.uk
UK Unique Taxpayer Reference (UTR)
Current Individuals Entities

HM Revenue & Customs (HMRC)

Ten-digit tax reference assigned by HMRC to taxpayers in regimes such as Self Assessment and to entities such as partnerships, trusts, and companies in Corporation Tax.

Details
Examples
2234567890
Where to find it

On previous tax returns and other HMRC documents such as notices to file a return or payment reminders; for individuals it can also be found in the Personal Tax Account and HMRC app.

Common names
UTR Tax reference
Structure
1 Check digit Leading check digit derived from the remaining 9 digits using HMRC's weighted modulus-11 rule.
2-10 Body Nine numeric characters.
Official source
gov.uk design.tax.service.gov.uk raw.githubusercontent.com oecd.org
UK HMRC Charities Reference Number
Current Entities

HM Revenue & Customs (HMRC)

HMRC charity-tax reference used for charities recognised by HMRC for UK charity tax reliefs and accepted as the TIN when a charity does not have a CRN.

Details
Examples
AB12345 EW89386
Where to find it

On HMRC charity-tax correspondence and when registering, enrolling, or claiming through Charities Online.

Common names
HMRC charities reference Charity reference
Official source
gov.uk assets.publishing.service.gov.uk