What is Hong Kong’s Global Minimum Tax (GMT) / HKMTT?
Hong Kong has enacted the Inland Revenue (Amendment) (Minimum Tax for Multinational Enterprise Groups) Ordinance 2025, giving legal effect to OECD’s Pillar Two / GloBE rules. The law takes effect for fiscal years beginning on or after 1 January 2025. Under this regime, large multinational enterprise (MNE) groups with consolidated annual revenue of EUR 750 million or more are subject to a 15% minimum tax rate, enforced through two interlocking rules:
- Income Inclusion Rule (IIR): top-up tax may be imposed on parent entities for constituent entities taxed below the minimum.
- Undertaxed Profits Rule (UTPR): acts as a backstop where IIR doesn’t capture all shortfalls. Hong Kong introduces a HK Minimum Top-up Tax (HKMTT) to protect its taxing rights. (ird.gov.hk)
Compliance & Reporting Requirements
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Electronic filing mandated for profits tax returns of in-scope entities (corporate or non-corporate) whose fiscal years begin on or after 1 April 2025 (i.e. 2025/26 onwards). Paper filing allowed only for certain winding-up, amalgamating, or exceptional cases. (ird.gov.hk)
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Pillar Two Portal: Part 4AA entities must file top-up tax notifications, apply for group and joint venture codes, and may designate a local Hong Kong constituent entity to file certain returns on behalf of others. (ird.gov.hk)
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Use of GIR (GloBE Information Return) schema and safe harbour provisions to simplify reporting burden. Hong Kong has signed a GIR MCAA to allow group filings where possible. (ird.gov.hk)
Practical Strategies for In-Scope MNEs
- Review your corporate structure to identify low-tax jurisdictions in your group and anticipate where top-ups may apply.
- Ensure your financial reporting and tax compliance systems track effective tax rate (ETR) at the jurisdictional level.
- Evaluate whether to reorganize or restructure holding entities or operations to minimize exposure under UTPR, where apportionments of headcount/tangible assets come into play.
- Explore eligibility for safe harbour or simplified filing where possible.
Example Scenario
Suppose MNE Group X has a subsidiary in Jurisdiction Y taxed at 10%, and Hong Kong constituent entities taxed at 12%; other jurisdictions meet or exceed 15%. Under Pillar Two, HK-parent may face a top-up payable equivalent to the shortfall to reach 15% in Y, but if Hong Kong adopts a QDMTT safe harbour, the HKMTT may allow local bottom-line adjustments. Entity X should also use GIR returns correctly to reflect low ETRs in foreign subsidiaries.
Key Dates & Action Items
- Identify in-scope groups for tax years beginning 1 Jan 2025 onward.
- Prepare notifications via Pillar Two Portal—get required group/JV codes.
- Update accounting methods and gather jurisdictional tax statistics.
- Monitor legislative developments for any further refinements or compliance guidance.
Implementing the GloBE rules is a major shift for large international groups. With thoughtful preparation and strong internal governance, navigating the global minimum tax regime can be smoothly managed rather than reactive.