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Hong Kong

Hong Kong uses TIN-equivalent identifiers for AEOI purposes: the Hong Kong Identity Card number for individuals and the 8-digit Business Registration Number for entities.

HK HKG 2 TIN types Last reviewed 2026-05-14

TIN types

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

Validate Hong Kong TIN
Hong Kong Identity Card Number (HKID)
Current Individuals

Immigration Department (Hong Kong Special Administrative Region Government)

Official identity-card number used as the TIN-equivalent for Hong Kong tax-resident individuals in AEOI self-certifications.

Details
Examples
A123456(3) AB123456(9)
Where to find it

At the bottom right-hand corner of the Hong Kong identity card.

Common names
HKID Hong Kong Identity Card number
Structure
1 or 1-2 Prefix One or two capital letters that start the HKID number.
2-7 or 3-8 Serial Six numeric characters.
Final bracketed character Check character Digit or letter shown in brackets and included in the TIN-equivalent without brackets.
Official source
ird.gov.hk oecd.org immd.gov.hk digitalpolicy.gov.hk github.com
Hong Kong Business Registration Number (BRN)
Current Entities

Business Registration Office, Inland Revenue Department (IRD)

Eight-digit Business Registration Number used as the TIN-equivalent for Hong Kong tax-resident entities in AEOI self-certifications.

Details
Examples
12345678 99999999
Where to find it

At the front of the Business Registration Certificate number, shown in the middle of the certificate under the heading "Certificate No.".

Common names
BRN Business Registration Number Unique Business Identifier UBI
Structure
1-8 Business Registration Number Eight numerals at the front of the Business Registration Certificate number.
Official source
ird.gov.hk oecd.org cr.gov.hk gov.hk