A Guide to Global Minimum Tax in Hong Kong – Compliance Requirements for MNEs (Part II)

Pillar Two Compliance in Hong Kong requires constituent entities of in-scope MNE groups to meet specific filing obligations, deadlines, and mandatory e-filing requirements under the GloBE rules and Hong Kong minimum top-up tax (HKMTT). With the regime now operational, this guide covers the top-up tax return and notification procedures, penalties for non-compliance, mandatory e-filing through the IRD’s Pillar Two Portal, and key practical considerations for MNEs preparing for their first filing cycle.

Hong Kong began implementing the OECD’s Pillar Two global minimum tax rules for fiscal years starting on or after January 1, 2025. The rules, which generally apply to the Hong Kong-based constituent entities of multinational enterprise (MNE) groups with consolidated annual revenue of at least €750 million in two of the last four fiscal years, impose new reporting and top-up tax obligations under the GloBE rules and the Hong Kong minimum top-up tax (HKMTT). 

With the regime now in force, in-scope MNEs should begin preparing early asHong Kong requires both an annual top-up tax notification and a top-up tax return, with deadlines determined by the group’s reporting fiscal year-end. On January 19, 2026, the Inland Revenue Department (IRD) launched the first phase of the Pillar Two Portal, requiring electronic submission of required top-up tax returns and notifications and marking the start of Hong Kong’s mandatory e-filing framework for Pillar Two compliance. 

This is the second in our two-part series on Hong Kong’s implementation of the Pillar Two global minimum tax. To see the requirements for companies in Hong Kong under the GloBE rules, see Part I: A Guide to Global Minimum Tax in Hong Kong – Understanding the Rules for MNEs.

Compliance procedures for in-scope MNEs and constituent entities in Hong Kong 

Filing top-up tax returns 

No later than 15 months after the last date of the reporting fiscal year, Hong Kong-based constituent entities of in-scope MNEs are required to submit a single top-up tax return for the purposes of the GloBE rules and HKMTT. However, the filing deadline for the first transition year has been extended to 18 months from the end of the reporting year. 

For the first transition year of any constituent entities of an MNE group, the filing deadline has been extended to 18 months after the last day of the reporting fiscal year. In practice, groups should map their reporting fiscal year-end to the 15‑month (or 18‑month transition year) deadline and align local Hong Kong filings with the group’s overall GloBE reporting timetable.

Find Business Support

Our experts help businesses manage corporate tax, compliance, and transfer pricing across Asia's jurisdictions.

The top-up tax return includes the information required in the standardized GloBE Information Return (GIR).   

Hong Kong constituent entities can be relieved from the obligation to file the GIR information if the required information has already been filed in another jurisdiction that will be able to exchange GIR information with Hong Kong under a qualifying competent authority agreement.  

Moreover, if an in-scope MNE has more than one constituent entity in Hong Kong, the entities can designate one entity to file the top-up tax return to the IRD. This entity must be appointed annually, and allows all other Hong Kong constituent entities of the group to be relieved of their filing obligation. 

An assessor may require a constituent entity to provide information on whether the information provided in the top-up tax return is accurate and complete. Failure to comply may trigger penalties under the Inland Revenue Ordinance. 

Filing of top-up tax notification 

In addition to the top-up tax return, each Hong Kong constituent entity of an in-scope MNE group is required to file an annual top-up tax notification in a prescribed form and manner within six months after the last day of the reporting fiscal year. The notification must detail its obligations for filing a top-up tax return and is intended to inform the IRD of that the MNE is in scope of the GloBE rules and HKMTT and that the constituent entities is within the jurisdiction of Hong Kong for the purpose of the top-up tax filing obligations.  

As with the top-up tax return, where there are multiple constituent entities of an in-scope MNE, they can appoint one entity to handle the filing procedures. 

The notification must include (but is not limited to) the following information: 

• The name, address, and business registration number of each of the MNE’s Hong Kong constituent entities;
• If the MNE’s ultimate parent company is located in a jurisdiction other than Hong Kong, the jurisdiction the in-scope MNE’s ultimate parent company is located and its name, address, and business registration number;
• Whether the GloBE filing is intended to be effected in Hong Kong for the fiscal year, and if so, the name, address, and business registration number of the entity designated to handle the filing in Hong Kong; and
• Whether the GloBE filing is intended to be effected outside of Hong Kong for the fiscal year, and if so, the jurisdiction in which the GloBE information return will be filed, and the name, address, and business registration number of the entity designated to handle the filing in that jurisdiction. 

Penalties for non-compliance 

A constituent entity that fails to file the top-up tax return or top-up tax notification is liable for a fine at level 3 under the Criminal Procedure Ordinance (up to HK$10,000/US$1,279) and a further fine that is three times the amount of undercharged top-up tax.

Find Business Support

We provide technology-driven accounting and compliance solutions tailored to Asia's diverse markets.

Meanwhile, a constituent entity that fails to comply with an assessor’s request to provide additional information on a top-up tax return may be liable to a level 3 fine. 

If a constituent entity files, or knowingly allows to be filed on its behalf, a top-up tax return or notification that is misleading, false, or inaccurate, or provides misleading, false, or inaccurate information regarding an MNE’s top-up tax liability, may be liable for a level 3 fine and a further fine of three times the amount of undercharged top-up tax. 

Mandatory electronic filing 

The top-up tax returns and notifications must be filed electronically through the Pillar Two Portal by the designated constituent entity. This Pillar Two Portal is an extension of the Business Tax Portal and is accessed through the latter platform. 

These mandatory electronic filing procedures are being implemented in two phases: 

• Phase one: Launched on January 19, 2026, for designated entities to file the top-up tax notification.
• Phase two: To be launched in the fourth quarter of 2026 for designated entities to file the top-up tax return, as well as for the entities to view and download notices of top-up tax assessments. 

Entities tasked with filing these documents must register their designated business accounts under the Business Tax Portal to access the Pillar Two Portal directly. The individuals tasked with signing and submitting top-up tax notifications and returns on behalf of the entity must use their e-cert (Organisational) with AEOI Functions for the purposes of authentication. 

Mandatory e-filing of profits tax return 

In addition to the top-up tax return, certain applicable constituent entities of in-scope MNEs are also required to file their profits tax return for a year of assessment (YA) beginning on or after April 1, 2025.  

The mandatory e-filing applies to: 

• Profits Tax Return – Corporations (BIR 51); and
• Profits Tax Return – Persons Other Than Corporations (BIR 52). 

Constituent entities that are subject to the mandatory e-filing of profits tax returns are those that meet both of the following criteria: 

1. The entity is a Part 4AA entity of an MNE (see Part I) for a fiscal year beginning on or after January 1, 2025, corresponding to the applicable YA.
2. The MNE to which the Part 4AA entity is an in-scope MNE for a fiscal year beginning on or after January 1, 2025, corresponding to the applicable YA, or preceding the fiscal year corresponding to the applicable YA. 

A “fiscal year corresponding to the applicable YA” refers to the fiscal year of the MNE group within which the basis period of the YA of the entity ends (the YA beginning on or after April 1, 2025). 

The e-filing system adopts a “once-in, always-in” mechanism, meaning that if an entity is required to e-file a profits tax return under phase one for a given year of assessment (YA), it will be required to e-file this tax return for every subsequent YA. This applies regardless of whether the entity meets the two above conditions for any subsequent YA. It will generally also apply to entities subject to the phase one filing requirements that subsequently leave an in-scope MNE, as well as to those entities whose MNEs subsequently become out of scope. 

Exemptions

Entities may be subject to the phase one mandatory e-filing requirements, and may be permitted to file the profits tax return in paper form in the following circumstances: 

1. It is being wound up or amalgamated pursuant to the Companies (Winding Up and Miscellaneous Provisions) Ordinance or Companies Ordinance;
2. It has no record in the Business Register;
3. It has notified the Companies Registry or Business Registration Office of its date of cessation;
4. The accounting period of its financial statement that is to be submitted with the profits tax return exceeds 12 months;
5. The profits tax return for the YA 2025/26 is issued on or before March 31, 2026; or
6. For the purposes of refiling a profits tax return previously e-filed but found to be invalid. 

Any supplementary forms must still be filed electronically. 

Considerations for MNEs 

With Hong Kong’s Pillar Two compliance framework now operational, in-scope MNEs should ensure that internal processes, responsible entities, and electronic filing access are fully in place. This includes confirming which Hong Kong constituent entity will be designated for filings, aligning reporting timelines with group-level compliance obligations, and preparing for mandatory e-filing through the Pillar Two Portal and the Business Tax Portal.

Related Reading

Hong Kong Employer’s Return 2026 Opens: Are You Ready?

Jennifer Lu, Partner at Dezan Shira & Associates, emphasizes that the primary Pillar Two risk for MNEs in Hong Kong lies less in technical interpretation and more in execution. Common challenges arise where group‑level GloBE calculations are not fully aligned with local Hong Kong filing requirements, where internal ownership of Pillar Two compliance is unclear across tax and finance teams, or where portal registration and access arrangements are addressed too late in the process. 

From an advisory perspective, we recommend that in‑scope MNEs approach Pillar Two compliance as an ongoing governance and operational exercise, rather than a one‑off filing obligation. As a practical next step, many groups benefit from conducting an early readiness review, covering scope confirmation, designation of Hong Kong filing entities, data availability, internal review and sign‑off processes, and access to the Pillar Two Portal. Taking these steps well ahead of the first notification and filing deadlines can materially reduce execution risk, avoid last‑minute remediation, and provide management with greater certainty over compliance outcomes.  

Tax planning and compliance in Hong Kong require careful navigation of evolving local and international tax rules. Our experienced advisors support businesses with corporate tax, indirect tax, individual tax, international tax, and transfer pricing, helping them remain compliant while optimizing their tax position in Hong Kong and the wider Asia?Pacific region.

Jennifer Lu

Partner

Talk to an expert at Hongkong@dezshira.com

Or request a consultation at +852 2376 0335

• Previous Article China Customs Compliance Alert: GAC’s New Credit Management Rules Effective April 1
• Next Article