Hong Kong Tax Identification Number (TIN) for Individuals and Companies.

Hong Kong has no separate TIN

Hong Kong does not issue a dedicated tax identification number. When a bank, broker, insurer or overseas form asks for your tax identification number in Hong Kong, the Inland Revenue Department (IRD) treats two numbers you already hold as the equivalent: the Hong Kong Identity Card (HKID) number for individuals, and the Business Registration (BR) number for companies and other entities. The rule is set out on the IRD's page on residency for tax purposes and TINs, written for automatic exchange of financial account information (AEOI), the system behind the Common Reporting Standard (CRS) forms that banks hand out.

Source: Inland Revenue Department and Companies Registry. Checked October 2026.

There is nothing to apply for. The harder part is telling these numbers apart from the others on your paperwork.

Tax identification number in Hong Kong for individuals: the HKID number

For an individual who is tax resident in Hong Kong, the TIN is the HKID number. The IRD asks for all of its letters and digits, including the character in brackets, but without the brackets.

An HKID number is one or two letters and six digits, followed by a check digit that is either a numeral from 0 to 9 or the letter A, according to the government's HKID number data standard. Using the sample from that standard, A123456(A) goes on a self-certification form as A123456A.

For AEOI purposes, an individual is tax resident in Hong Kong if they ordinarily reside in Hong Kong, or stay more than 180 days in a year of assessment, or more than 300 days in two consecutive years of assessment one of which is the relevant year. Hong Kong residents aged 11 or over must register for an identity card unless they are exempt or excluded, the Immigration Department says, so most adults who meet those tests hold an HKID number. The usual gaps are children under 11 and people who have only just arrived.

The TIN on your tax return is an eTAX login

This is an easy mix-up. Your individual tax return (BIR60) and your notice of assessment both print a "TIN", but the IRD's AEOI frequently asked questions state that this number is solely for logging in to eTAX and the IRD's e-services, is not a tax identifier of a Hong Kong tax resident, and should not be provided for AEOI purposes.

The IRD now labels it "TIN (for eTAX login)". On the Individual Tax Portal, new users request an access code with that TIN plus either their HKID number or their Individual Tax File Number, which is a third number again: the IRD's reference for your tax file. Neither the eTAX TIN nor the file number is on the IRD's list of Hong Kong TIN equivalents.

Source: Inland Revenue Department and Companies Registry. Checked October 2026.

The eTAX TIN and file number matter when you file your own return or appoint someone to help with salaries tax in Hong Kong. On a bank's CRS form, only the HKID number belongs.

Companies and other entities: the Business Registration number

For a company or other entity that is tax resident in Hong Kong, the TIN is its BR number. In the IRD's words, it is the 8 numerals at the front of the BR certificate number. The digits after them are not part of it.

The same eight digits now identify the company at the Companies Registry. Since 27 December 2023, the BR number has been the Unique Business Identifier for companies and other entities administered by the Registrar of Companies, replacing the former Company Registration number. Certificates of Incorporation issued since then show the BR number as the certificate "No.". Older companies keep their existing certificates, and the Companies Registry offers a CR No. / BRN Mapping search and downloadable lists to match an old company number to its BR number.

Two cases need more care:

• Dummy BR numbers. Companies registered before 27 December 2023 that never held a BR number, such as those exempt from business registration, were given a dummy BR number with a letter prefix. The IRD notes that these companies have no record in its Business Register. How such a company completes a self-certification is a question for a tax advisor.
• Another business's BR number. If a form asks for a supplier's or counterparty's number, the IRD's Business Registration Number Enquiry service on GovHK looks it up from the full business name and its location.

A new company receives its BR certificate together with its Certificate of Incorporation through the one-stop filing described in the guide to company registration in Hong Kong. If a certificate has lapsed or its particulars are out of date, providers of business registration services in Hong Kong can handle renewals and changes.

If you do not have an HKID or BR number

The IRD asks for every jurisdiction where you are tax resident and "the corresponding TIN (if applicable)", so a missing Hong Kong number is not automatically a problem. What the form needs depends on why you do not have one.

Each financial institution designs its own self-certification form, so the way to explain a missing TIN varies between banks. On the reporting side, the IRD tells institutions that do not hold a TIN to leave the TIN field blank rather than enter NIL, 0 or a placeholder letter.

If you have just arrived on one of the Hong Kong visa options and your identity card has not been issued yet, ask the bank how it wants the form completed in the meantime. Once the card arrives, its number is your Hong Kong TIN.

How banks use your TIN under CRS

A Hong Kong financial institution needs a self-certification for every account opened on or after 1 January 2017: a formal declaration of your tax residence, with a TIN for each jurisdiction. For older accounts, the institution asks when it has doubts about where you are resident.

Reporting is narrower than the form might suggest. Hong Kong is not a reportable jurisdiction of its own. A bank reports an account to the IRD only when the holder (or, for some companies, a person who controls it) is tax resident in one of the reportable jurisdictions, a list of more than 120 places that includes the Chinese Mainland, Singapore and the United Kingdom, and the IRD passes the information to that jurisdiction's tax authority. If you are tax resident only in Hong Kong, your account is not reported. A reported account carries your name, address, jurisdiction of residence, TIN and date and place of birth, with the year-end balance and income such as interest and dividends.

Three points matter for the account holder:

• Accuracy. Knowingly or recklessly giving a statement in a self-certification that is materially misleading, false or incorrect is an offence, punishable on conviction by a fine at level 3 (HK$10,000).
• Updates. If your tax residence changes, the IRD expects you to give the institution an updated self-certification, generally within 30 days.
• Refusal. If you refuse to let the institution release your information for AEOI, the IRD says the institution may have to consider whether to keep the account open.

A company's form asks one more question: its CRS classification. If the company is a passive non-financial entity (NFE), the bank also looks through to its controlling persons, the individuals who control it, and records each one's tax residence and TIN. For a company, the IRD's threshold for identifying controlling persons is 25%. Banks test the classification against what they know, so an investment holding company with a discretionary mandate may be asked whether it is really a financial institution. The IRD expects a bank in that position to obtain recent financial statements to confirm the classification. A tax advisor or a corporate lawyer in Hong Kong can review the classification before the form is signed.

AEOI changes from 2027 and a bill still pending

The Inland Revenue (Amendment) (Automatic Exchange of Information) Ordinance 2026 takes effect on 1 January 2027. It requires every reporting financial institution in Hong Kong to register on the IRD's AEOI Portal and tightens record keeping and sanctions. These are obligations on the institutions themselves.

A second amendment bill, gazetted on 22 May 2026, would go further. Subject to its passage, the Crypto-Asset Reporting Framework (CARF) would apply from 1 January 2027, with crypto-asset service providers collecting self-certifications from their users, and an amended CRS would apply from 1 January 2028. Among other changes, the amended CRS would expressly require account holders to self-certify every jurisdiction of tax residence, which the IRD's current guidance already asks for. Neither measure is in force yet: when this guide was checked in October 2026, the IRD still described both as part of a bill under scrutiny by the Legislative Council.

Proof of tax residence is a separate document

Some overseas forms want more than a number. To claim tax benefits under one of Hong Kong's comprehensive double taxation agreements, you may need proof that you are a Hong Kong resident. The IRD issues a Certificate of Resident Status for this, with online applications through eTAX. It generally does not sign or stamp other jurisdictions' own forms, except those of Austria, Belgium and Luxembourg.

When a tax advisor helps

Once you know which number to use, the questions that still need judgment are about residence: two places of residence at once, a move part-way through the year, a company incorporated in one place and managed from another, or a holding structure with controlling persons in several jurisdictions. Tax advisors in Hong Kong handle residence, treaty and IRD questions like these.

This guide is general information about tax identification numbers in Hong Kong. It is not tax or legal advice. For a specific situation, speak with a qualified professional.