Base Erosion and Profit Shifting (BEPS) refers to tax planning strategies used by multinational enterprise (MNE) groups to shift profits to low‑ or no‑tax jurisdictions, eroding the tax base of countries where real economic activity occurs. Pillar Two, part of the OECD’s BEPS 2.0 initiative, introduces a global minimum effective tax rate of 15% to ensure that large MNEs pay a fair share of tax in each jurisdiction where they operate. At the heart of Pillar Two are the GloBE (Global Anti‑Base Erosion) Rules, a coordinated set of calculations and mechanisms, including:
- Qualified Domestic Minimum Top‑Up Tax (QDMTT),
- the Income Inclusion Rule (IIR), and
- Undertaxed Profits Rule (UTPR).
These mechanisms determine whether an additional “top‑up” tax is required to bring a jurisdiction’s effective tax rate up to the minimum level.
Pillar Two is no longer a future policy consideration for large multinational enterprise (MNE) groups; it is now an active compliance requirement with defined Hong Kong filing deadlines and new administrative procedures.
This guide distils the latest Hong Kong Inland Revenue Department (IRD) guidance and leading professional insights into a single, action‑oriented resource for tax directors, controllers and compliance leads.
Key Takeaways: Hong Kong Pillar Two Implementation
- Hong Kong implemented the OECD Pillar Two global minimum tax through the Inland Revenue (Amendment) (Minimum Tax for Multinational Enterprise Groups) Ordinance 2025 (the Amendment Ordinance).
- The Amendment Ordinance introduces the Hong Kong Minimum Top-Up Tax (HKMTT), designed to operate as a Qualified Domestic Minimum Top-Up Tax (QDMTT), together with the Income Inclusion Rule (IIR).
- The rules apply to multinational enterprise (MNE) groups with consolidated annual revenue of at least EUR 750 million in at least two of the four preceding fiscal years.
- The Hong Kong minimum tax framework applies to fiscal years beginning on or after 1 January 2025, while the Undertaxed Profits Rule (UTPR) will be introduced later.
- Hong Kong constituent entities must file a top-up tax notification within six months after the end of the reporting fiscal year.
- The GloBE Information Return (GIR) and Hong Kong top-up tax return must generally be filed within 15 months of fiscal year-end (or 18 months in the first year of application).
Key Pillar Two Definitions
- GloBE Rules – The Global Anti-Base Erosion rules, which seek to ensure that large multinational enterprise (MNE) groups pay a minimum tax of 15% on profits derived from every jurisdiction where they operate.
- QDMTT (Qualified Domestic Minimum Top-Up Tax) – A domestic minimum tax that allows a jurisdiction to collect top-up tax on low-taxed profits before other jurisdictions apply the IIR or UTPR.
- HKMTT (Hong Kong Minimum Top-Up Tax) – Hong Kong’s implementation of the QDMTT under the Inland Revenue (Amendment) (Minimum Tax for Multinational Enterprise Groups) Ordinance 2025.
- IIR (Income Inclusion Rule) – The primary rule under GloBE which imposes a top-up tax on the parent entity of an in-scope MNE group in respect of its low-taxed constituent entities (where the effective tax rate is below 15%) located outside the parent’s jurisdiction.
- UTPR (Undertaxed Profits Rule) – A backstop rule to the IIR that ensures top-up tax is charged and collected where it is not brought into charge under the IIR.
- GloBE Information Return (GIR) – A standardized return developed under the OECD’s GloBE implementation framework.
Who Must Comply With Hong Kong Pillar Two Rules?
Hong Kong Implementation
Hong Kong enacted the Inland Revenue (Amendment) (Minimum Tax for Multinational Enterprise Groups) Ordinance 2025 (Amendment Ordinance) on 6 June 2025. The Income Inclusion Rule (IIR) and Hong Kong’s version of the QDMTT—the Hong Kong minimum top-up tax (HKMTT)—apply for fiscal years beginning on or after 1 January 2025. The UTPR will be introduced on a date to be announced by Gazette notice.
Revenue Threshold
Pillar Two applies to MNE groups with annual consolidated revenue ≥ EUR 750 million in at least two of the four fiscal years preceding the current fiscal year (translated using December ECB exchange rates for non-Euro groups). That threshold is embedded in Hong Kong’s legislation and mirrors the OECD’s GloBE model rules.
Entity “Location” & Residence Definition
Under the OECD’s GloBE rules, it is crucial to determine exactly where an entity is “located” because that determines which jurisdiction has the primary right to collect the top-up tax. The OECD rules state that an entity is located in the jurisdiction where it is considered a “tax resident” based on its place of management, creation, or similar criteria.
Historically, Hong Kong has operated on a territorial tax system, meaning tax is based on where profits arise, rather than a strict statutory definition of “tax residency” for general domestic purposes.
However, to ensure that the GloBE rules recognize entities as being located in Hong Kong, the government formally added Section 2(11) to the Inland Revenue Ordinance (IRO) by the Amendment Ordinance. This establishes a clear, statutory definition: an entity is a tax resident if it is a company incorporated in Hong Kong, or if incorporated elsewhere, it is normally managed or controlled in Hong Kong (with similar rules for non-company entities).
Instead of creating a definition solely for Pillar Two, Hong Kong decided to make this definition apply to the general purposes of the IRO, aligning this wording with the definition of a “resident” already used in Hong Kong’s Comprehensive Avoidance of Double Taxation Agreements (CDTAs).
By making it a general, standardized definition that mirrors tax treaties, Hong Kong establishes a robust, internationally recognized standard of tax residency. It ensures cohesion across domestic tax administration, international tax treaties, and the new global minimum tax framework.
While Hong Kong is implementing its minimum top-up tax starting in 2025, many other jurisdictions around the world started implementing the GloBE rules on 1 January 2024. As such, the definition of a Hong Kong tax resident takes retrospective effect from 1 January 2024. This ensures that Hong Kong constituent entities are officially regarded as located in Hong Kong throughout the 2024 fiscal year, thereby minimizing their exposure to top-up tax in other jurisdictions that implemented the rules early.
Local Compliance Obligations for In-Scope Entities
If your group is in scope, expect your Hong Kong constituent entities to have local compliance obligations—namely an annual “top-up tax notification” and a “top-up tax return”—even if the global computation and the GloBE Information Return (GIR) are prepared centrally by the ultimate parent. However, groups can ease this burden by appointing a “Designated Local Entity” to file on behalf of all Hong Kong members. The IRD’s Pillar Two Portal is the channel for these submissions, with Phase 1 (for notifications) currently active, and Phase 2 (for tax returns) launching in Q4 2026.
QDMTT vs. Global GloBE Top-up: Understanding the Local Layer
Priority of Collection (QDMTT First)
Under the GloBE architecture, a jurisdiction has the first priority to collect any top‑up tax on low‑taxed profits arising locally if it has implemented a Qualified Domestic Minimum Top-up Tax (QDMTT).
If the local jurisdiction fails to implement a QDMTT, other foreign jurisdictions where the MNE operates are authorized to step in and collect that tax instead through secondary mechanisms known as the Income Inclusion Rule (IIR) or Undertaxed Profits Rule (UTPR).
Hong Kong’s QDMTT is intended to function as such a QDMTT, which means any shortfall to the 15% minimum on Hong Kong profits should be settled in Hong Kong first.
Interlocking Rules
Once QDMTT has brought Hong Kong’s jurisdictional effective tax rate (ETR) to the minimum, there should be no residual top‑up under another jurisdiction’s IIR/UTPR for the Hong Kong basket (subject to crediting rules and the quality of the domestic regime). Hong Kong’s legislation incorporates the OECD Model Rules with limited adaptations and treats top‑up tax as profits tax for administration, assessments, payment and objections.
GIR vs. Local Filings
The GloBE Information Return (GIR) is a standardized information return template developed under the OECD’s GloBE implementation framework. The standard deadline to file this return is within 15 months of year‑end (or 18 months for the first in‑scope year in a jurisdiction).
Rather than forcing a multinational enterprise (MNE) group to submit the full GIR in every single country where it operates, the system relies on coordinated filing and exchange mechanisms. If the GIR is filed by the Ultimate Parent Entity (or a designated filing entity) in a jurisdiction outside Hong Kong, that information can be automatically exchanged with Hong Kong under a Qualifying Competent Authority Agreement, such as the Multilateral Competent Authority Agreement on the Exchange of GloBE Information (GIR MCAA).
Despite the global exchange of the GIR, Hong Kong constituent entities still have local obligations. They must electronically submit their filings using the Inland Revenue Department’s designated system, known as the Pillar Two Portal. The local obligations consist of two parts:
- Top-up tax return: This single local return contains the necessary GIR information and must be filed following the exact same GIR timetable. If the GIR is exchanged with Hong Kong via the MCAA mentioned above, the local entities are relieved from having to resubmit that specific GIR information locally.
- Top-up tax notification: This is an earlier requirement used to notify the IRD of the group’s status and identify the entity that will submit the GIR. It is due within 6 months after the last day of the fiscal year.
Group filing mechanics: To reduce the compliance burden, Hong Kong allows for “group local filing”. If an in-scope MNE group has multiple entities in Hong Kong, they do not all have to file separately. The group can appoint one of its local entities to act as the “designated local entity”. Once this designated entity files the top-up tax notification and the top-up tax return on behalf of the group, all other Hong Kong constituent entities are relieved of their individual filing obligations.
Why You Still Need a Hong Kong Advisor—Even If Calculations Are Centralised
Local Law and Portal Processes
Group engines typically produce robust jurisdictional ETR measures and GloBE income/covered tax reconciliations, but the Hong Kong filing is governed by Schedules 61–63 of the amendment ordinance and IRD administrative practice (Portal access, MNE/JV codes via Form IR1485, and e‑cert (Organisational) with AEOI functions). Advisors ensure your data maps cleanly to Hong Kong’s definitions and documentary requirements.
Staying Current With Guidance
Hong Kong’s law is designed to track OECD commentary and administrative guidance, with updates incorporated through subsidiary legislation, so apparent “global rules” can change in ways that affect local computations (e.g., Article 9.1 guidance on deferred taxes). Monitoring this and translating it into filing‑ready workpapers is a local task.
Operational Logistics
Hong Kong’s mandatory e‑filing for profits tax returns (PTRs) applies to all Hong Kong constituent entities of in‑scope groups from YOA 2025/26. In late September 2025, the IRD sent bulk letters to potentially in‑scope groups to kick off registrations and code applications. Local advisors help you respond on time and avoid technical snags.
What to Give Your Hong Kong Filing Agent: A Clean, Complete Data Pack
To minimise recomputation and keep fees predictable, compile:
- Hong Kong ETR pack (jurisdictional): GloBE income/loss, adjusted covered taxes, substance‑based exclusion, top‑up percentage, and safe harbour positions for Hong Kong.
- Reconciliations: statutory accounts ↔ GloBE income and covered taxes; Deferred Tax Asset (DTA)/ Deferred Tax Liabilities (DTL) roll‑forwards with Article 9.1 impacts tracked.
- Elections & safe harbours: list the group‑level elections (and where Hong Kong relies on them) plus any transitional safe harbours invoked.
- Entity list & structure: Hong Kong constituent entities, stateless entities/PEs, JVs/JV subsidiaries, Tax Identification Numbers (TINs), and status under GloBE for consistency with the GIR.
- Compliance logistics: copies of IR1485 (MNE/JV codes), e‑cert details, Business Tax Portal credentials, and named authorised user for the Pillar Two Portal.
- Central filing evidence (if applicable): GIR central filing jurisdiction, MCAA coverage, and (where requested) notification that GIR data will be exchanged to Hong Kong.
Non-Negotiable Deadlines in Hong Kong
Top-up Tax Notification (Hong Kong)
Each Hong Kong constituent entity of an in‑scope MNE must file a “top‑up tax notification” within 6 months of the reporting fiscal year‑end—electronically via the Pillar Two Portal (phase one live 19 January 2026).
Top-up Tax Return (Hong Kong)
The Hong Kong top‑up return is due by the GIR deadline; group filing is permitted if conditions (e.g., designated filer, exchange relationships) are satisfied.
GIR Deadline (OECD)
The GIR is due within 15 months of year‑end (or 18 months for the first in‑scope year in a jurisdiction), with a transitional policy that initial obligations would not fall due before 30 June 2026.
Calendar Year Illustration
If your first in‑scope year is FY2025 (ending 31 Dec 2025):
- Hong Kong notification by 30 June 2026 (6 months).
- Top‑up return/GIR by 31 March 2027 (15 months) or 30 June 2027 (18 months) depending on first‑year status.
Mandatory E-filing of PTRs
From Y/A 2025/26, Hong Kong constituent entities of in‑scope MNEs must e‑file profits tax returns; the IRD’s late‑September 2025 letters set the registration steps and two‑month reply expectation.
Penalties, Scrutiny and Governance
Penalty Framework
The QDMTT is administered as profits tax, so existing mechanisms for assessments, collection, objections and penalties apply. Expect closer audit scrutiny where Hong Kong filings diverge from the GIR or where reconciliations for deferred tax are weak.
Anti-Avoidance
Hong Kong removed the draft “main purpose test” and instead applies the Section 61A GAAR (sole/dominant purpose) with tailored modifications for top‑up tax (e.g., considering changes in overall group top‑up tax). This reduces ambiguity but heightens the importance of substance evidence and commercial rationale.
Recurring Risk Areas
- Deferred tax (Article 9.1). Transitional guidance caps/limits how DTAs feed into ETRs; poor tracking can materially swing outcomes.
- Safe harbours. Incorrect reliance or inconsistent application between GIR and QDMTT can lead to enquiries; keep a single register of elections and safe harbour determinations.
- Stateless/JV entities. Confirm “location” and status are consistent across GIR and HK returns.
Hong Kong Specific Nuances You Should Plan For
Portal Mechanics and Authentication
The Pillar Two Portal (within Hong Kong’s Business Tax Portal) is the venue for notifications and returns. In‑scope groups must secure MNE/JV group codes via Form IR1485 and authorise a filer holding an e‑cert (Organisational) with AEOI functions.
Record-Keeping
Maintain a complete audit trail to demonstrate consistency between local filings and the GIR (entity list, elections/safe harbours, ETRs, reconciliations). Hong Kong’s bilingual environment doesn’t change the need for clear, consistent documentation referencing GloBE concepts. (The IRD site is the anchor for updates on portal phases and guides.)
Territorial Principle Unchanged
The new residence definition is for GloBE purposes; it does not alter Hong Kong’s territorial source profits tax principle outside the minimum tax regime.
Coordinating QDMTT with Centralised Pillar Two Computations: An Operating Plan
A. Ownership & Oversight
Assign a Hong Kong filing owner (portal control, notifications/returns, PTR e‑filing), and brief the board/audit committee on the elections and safe harbours relevant to Hong Kong.
B. Calendar Integration
Lock in the 6‑month notification and the 15/18‑month GIR milestones, then back‑schedule data gathering and approvals. Where possible, freeze Hong Kong numbers before group GIR sign‑off to avoid post‑filing corrections.
C. Documentation Alignment
Create a Hong Kong annex to your global Pillar Two manual that covers: portal steps, IR1485 code process, e‑cert, notification/return timing, and PTR e‑filing.
D. Controls Checklist
Before every cycle: (1) MNE/JV codes validated, (2) e‑cert valid, (3) notification filed by month 6, (4) QDMTT return filed by GIR deadline, (5) PTR e‑filed for YOA 2025/26 onwards.
Safe Harbours: What They Are, How They Work, and Hong Kong Relevance
Purpose
Safe Harbours simplify Pillar Two compliance or reduce the need for full GloBE calculations. The OECD has issued evolving administrative guidance, updates to the GIR template, and transitional penalty relief aligned to safe harbours—all of which Hong Kong’s regime is designed to track through its legislative approach.
Key Categories to Encounter
- Transitional CbCR Safe Harbour: a temporary route using CbCR metrics and simplified covered taxes to deem certain jurisdictions out of top‑up where thresholds are met (e.g., sufficiently high CbCR‑based ETR).
- Simplified Calculations Safe Harbour: allows simplified covered tax and income computations during the transitional period instead of full GloBE mechanics.
- Substance‑based (“Routine Profits”) Safe Harbour: where the substance‑based income exclusion (based on payroll and tangible assets) is sufficient to eliminate excess profits, there is no top‑up tax for that jurisdiction.
- Domestic Minimum Top‑Up Tax Safe Harbour: where a jurisdiction’s domestic regime is qualified and the local top‑up is fully paid, groups may treat the jurisdiction as settled (i.e., no residual IIR/UTPR). This is the intended outcome for Hong Kong’s QDMTT once recognised as qualified.
Note: Always validate the current status of each safe harbour (including the “qualified” status of domestic regimes and the sunset of transitional measures) against the most recent OECD administrative guidance and Hong Kong’s adoption via subsidiary legislation.
What “Good” Looks Like for Your Hong Kong Pillar Two File
- Traceable data lineage: Statutory accounts → GloBE income and covered taxes, with DTA/DTL roll‑forwards reflecting Article 9.1 guidance.
- One register of elections/safe harbours: Same positions reflected in GIR and QDMTT to prevent mismatches.
- Administrative readiness: IR1485 submitted, codes confirmed, e‑cert live, portal access tested; 6‑month notification and GIR‑aligned return dates calendared.
- Governance evidence: Board/audit committee minutes approving elections and safe harbour reliance for Hong Kong.
- Cross‑border consistency: Papers evidencing QDMTT priority and the crediting of QDMTT to avoid double taxation under parent‑level rules.
A Six Month Action Plan (Hong Kong Focus)
Month 1–2: Scoping & setup
- Confirm in‑scope status (EUR 750m test) and list all Hong Kong constituent entities/JVs/stateless items.
- Apply for MNE/JV codes (IR1485); set portal access and register the e‑cert (Organisational with AEOI).
Month 2–3: Data & controls
- Build the Hong Kong ETR pack; prepare reconciliations and Article 9.1 DTA/DTL tracking.
- Decide and document safe harbour reliance (if any) and align with GIR schedules.
Month 3–4: Notification
- File the 6‑month top‑up tax notification via the Portal; keep submission receipts in the file.
Month 4–6: Returns & GIR alignment
- Draft the QDMTT return on the GIR timetable (15/18 months), check group filing eligibility.
- Ensure PTR e‑filing for Y/A 2025/26 is on track and consistent with your Pillar Two data.
Frequently Asked Questions: Hong Kong Pillar Two
When does Hong Kong implement Pillar Two?
Hong Kong’s minimum tax regime applies to fiscal years beginning on or after 1 January 2025.
What is the minimum tax rate under Pillar Two?
The global minimum effective tax rate under the OECD GloBE rules is 15%.
Which companies must comply with Hong Kong Pillar Two rules?
Multinational enterprise groups with consolidated revenue of at least EUR 750 million in two of the four preceding fiscal years.
When is the Hong Kong top-up tax notification due?
Within 6 months after the end of the reporting fiscal year.
How does Hong Kong’s HKMTT interact with the OECD global minimum tax rules?
Hong Kong’s Minimum Top-Up Tax (HKMTT) is designed to operate as a Qualified Domestic Minimum Top-Up Tax (QDMTT) under the OECD Pillar Two framework. This means Hong Kong has the primary right to collect any top-up tax on low-taxed profits arising within Hong Kong before other jurisdictions apply secondary mechanisms such as the Income Inclusion Rule (IIR) or Undertaxed Profits Rule (UTPR).
Can a multinational group file a single Hong Kong Pillar Two return for multiple entities?
Yes. Hong Kong allows group local filing. If an MNE group has multiple constituent entities in Hong Kong, it may appoint one entity as a Designated Local Entity to file the top-up tax notification and top-up tax return on behalf of all Hong Kong entities. Once the designated entity files, other local entities are generally relieved of separate filing obligations.
How is the Pillar Two global minimum tax rate calculated?
The calculation of the Pillar Two global minimum tax revolves around determining whether the Effective Tax Rate (ETR) of a multinational enterprise (MNE) group in a specific jurisdiction meets the minimum rate of 15%, and if not, computing a top-up tax to cover the shortfall.
Effective Tax Rate (ETR) = Adjusted Covered Taxes ÷ Net GloBE Income
- Adjusted Covered Taxes refers to the sum of the current tax expenses accrued by each constituent entity located in that jurisdiction, adjusted for specific additions, reductions, and temporary differences.
- Net GloBE Income is the sum of the GloBE income of all constituent entities in the jurisdiction minus the sum of the GloBE losses of all constituent entities in that jurisdiction.
Can Pillar Two safe harbours reduce Hong Kong compliance obligations?
Yes. The OECD has developed safe harbours to relieve in-scope MNE groups from performing full, complex GloBE calculations when certain conditions are met. In Hong Kong, these include the Transitional Country-by-Country Reporting (CbCR) Safe Harbour, the Transitional UTPR Safe Harbour, the QDMTT Safe Harbour, and the Simplified Calculations Safe Harbour for non-material constituent entities.
Conclusion: Turning Pillar Two into a Repeatable Hong Kong Process
With QDMTT and IIR effective for FYs starting 1 January 2025, and the Portal already live for notifications, Hong Kong’s implementation is moving from policy to practice. The main success factor is coordination—synchronising group‑level GIR work with Hong Kong’s 6‑month notification, GIR‑timed return, and mandatory PTR e‑filing requirements. Build the abbreviations table and safe harbour register into your internal manual; leverage the worked examples here to pre‑clear your positions with advisors; and keep a relentless focus on reconciliations and governance.
Hong Kong implemented the OECD Pillar Two global minimum tax through the Inland Revenue (Amendment) (Minimum Tax for Multinational Enterprise Groups) Ordinance 2025. The regime introduces the Hong Kong Minimum Top-Up Tax (HKMTT) and the Income Inclusion Rule (IIR) for fiscal years beginning on or after 1 January 2025. Multinational enterprise groups with global revenue above EUR 750 million must comply with new notification and filing obligations through the Inland Revenue Department’s Pillar Two Portal. Organisations with Hong Kong operations that may fall within the Pillar Two scope should begin preparing for the new compliance cycle well in advance of the first notification deadline. This typically includes confirming in-scope status, establishing internal data collection processes, and coordinating with Hong Kong advisors on portal registration and filing procedures. Early preparation helps reduce reconciliation issues and ensures alignment between group GIR reporting and Hong Kong’s local QDMTT requirements. If you have questions about how the Hong Kong Pillar Two regime may apply to your group, please reach out to our team for further discussion.
Disclaimer: This guide is general information, not advice. Always obtain advice tailored to your facts and current law/guidance before making decisions.