The Business Registration Number (BRN) is the 8-digit identifier issued by the Inland Revenue Department (IRD) to every business operating in Hong Kong. It appears on the Business Registration Certificate (BRC), serves as the company's tax identifier, and since December 2023 functions as the Unique Business Identifier (UBI) across all Hong Kong government departments. This guide explains what the BRN is, who needs one, where to find it, and how it differs from the Company Registration Number (CRN). For the full company formation process, see how to register a company in Hong Kong.
Highlights of this article
- The BRN is an 8-digit number issued by the IRD to all businesses in Hong Kong, including sole proprietorships, partnerships, limited companies, and foreign company branches.
- Since December 27, 2023, the BRN has been designated as the Unique Business Identifier (UBI) and Tax Identification Number (TIN) for all cross-departmental government interactions.
- The BRN appears on the Business Registration Certificate, which must be renewed annually or every 3 years. The BRN itself never changes.
- The BRN is distinct from the Company Registration Number (CRN), a 7-digit number on the Certificate of Incorporation that applies only to incorporated companies.
- Operating without a valid BRC is a criminal offence. Penalties include fines of up to HKD 5,000 and up to 1 year imprisonment.
What Is a Business Registration Number?
The BRN is the official identifier assigned to your business by the IRD under the Business Registration Ordinance (Cap. 310). Every business that carries on a trade, profession, or business for profit in Hong Kong must register with the IRD and obtain a BRC. The BRN is the unique number on that certificate.
Format: 8 consecutive digits (example: 12345678)
Issued by: Inland Revenue Department (IRD)
The BRN is permanent. It is assigned once and never changes, regardless of name changes, address changes, or changes in directors and shareholders. When you renew the BRC, only the certificate's validity dates are updated. The BRN stays the same.
Who Needs a Business Registration Number?
Under Cap. 310, all of the following must hold a valid BRC with a BRN:
- Private limited companies (obtained simultaneously with incorporation)
- Foreign companies operating a branch or representative office in Hong Kong
- Sole proprietorships
- General and limited partnerships
- Any person carrying on a trade, profession, or business for profit in Hong Kong
- Online and e-commerce businesses operating from Hong Kong
Exemptions:
- Charitable institutions exempt under Section 88 of the Inland Revenue Ordinance
- Licensed outdoor hawkers
- Pure agricultural, market gardening, or fishing activities
There is no revenue threshold. Any commercial activity requires registration within 1 month of commencing business. For the full business registration process for all entity types, see business registration in Hong Kong.
Where to Find Your Business Registration Number
The BRN appears on:
- The Business Registration Certificate (the physical or electronic certificate issued by the IRD), listed as "Certificate No."
- The Certificate of Incorporation (for companies incorporated after the one-stop registration service was introduced, both documents are issued simultaneously)
- Profits Tax Returns (Form BIR51) issued by the IRD
- The IRD eTax portal under your company's tax account
If you have lost your BRC, you can apply for a replacement at the Business Registration Office (1/F Revenue Tower, 5 Gloucester Road, Wan Chai) or through the IRD eTax portal. You can also verify a BRN through the IRD's Business Registration Number Enquiry Service.
What Is the BRN Used For?
The BRN is required across a wide range of official and commercial contexts:
| Use Case | Detail |
|---|---|
| Tax filings | Required on all Profits Tax Returns filed with the IRD |
| Corporate bank accounts | Banks require the BRC showing the BRN as part of KYC |
| Government forms and applications | The BRN is the standard identifier across government portals |
| Business licences | Most licence applications require the BRN as the business identifier |
| Invoicing | Commonly included on invoices to businesses for verification |
| Employer MPF registration | Required when registering as an employer with the MPF Authority |
| Government procurement | Tenders and contracts with government departments require the BRN |
The BRN as Unique Business Identifier (UBI) and TIN
On December 27, 2023, the IRD designated the BRN as the Unique Business Identifier (UBI) for Hong Kong. This has 2 practical effects:
Cross-departmental use. The BRN is now the single identifier used when a business interacts with any Hong Kong government department. Previously, different departments used different identifiers, creating duplication. The UBI reform standardises this.
Tax Identification Number function. The BRN now serves as the company's Tax Identification Number (TIN) for all IRD and international tax reporting purposes.
What did not change: The BRN numbers themselves were not changed. If your company had BRN 12345678 before December 2023, it still has BRN 12345678. The reform changed how the BRN is used, not the number itself.
What still uses the CRN: The Company Registration Number (7 digits) remains the identifier for Companies Registry filings, including Annual Returns and changes to company particulars. The BRN does not replace the CRN for Companies Registry purposes. For more detail on the difference, see BRN vs CRN in Hong Kong.
BRN vs CRN: Key Differences
| Feature | BRN | CRN |
|---|---|---|
| Digits | 8 | 7 |
| Issued by | Inland Revenue Department | Companies Registry |
| Who has it | All businesses | Incorporated companies only |
| Document | Business Registration Certificate | Certificate of Incorporation |
| Renewal | Annual or 3-year renewal required | No renewal (permanent) |
| UBI | Yes (since December 2023) | No |
| Tax identifier | Yes | No |
A sole proprietorship or partnership has a BRN but not a CRN. Only incorporated companies have both.
BRC Renewal and the BRN
The BRC must be renewed annually or every 3 years. The BRN does not change on renewal. Current fees from April 1, 2026:
| Certificate Type | Fee |
|---|---|
| 1-year BRC | HKD 2,350 |
| 3-year BRC | HKD 6,170 |
The IRD sends a demand note around 1 month before the BRC expiry date. Do not wait for the demand note. Renew before the expiry date to avoid penalties and banking disruption.
Consequences of Non-Registration or Expired BRC
Operating without a valid BRC is a criminal offence under Cap. 310:
| Breach | Penalty |
|---|---|
| Failure to register within 1 month of commencing business | Fine up to HKD 5,000 + backdated fees |
| Failure to renew BRC before expiry | Fine up to HKD 5,000 |
| Continued operation after formal notice | Prosecution and up to 1 year imprisonment |
Practical consequences beyond legal penalties:
- Banks treat an expired BRC as a KYC compliance failure. Some banks will freeze or close corporate accounts upon discovering an expired BRC.
- Government licences that require a valid BRC as a condition (e.g., money service operator) are suspended until the BRC is renewed.
- Entering major contracts, leases, or tenders requires a valid BRC.
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