Hong Kong Pillar Two Filing Guide

Summary

Hong Kong’s Pillar Two compliance model has three key aspects. First, an in-scope group needs portal access through the Business Tax Portal (BTP) and, where relevant, the Tax Representative Portal (TRP). Second, the group or its local filer needs a group identifier: an MNE code for the multinational group and, where applicable, a JV code for a Hong Kong standalone JV or JV group. Third, the group must deal with two annual Pillar Two filings in Hong Kong: the top-up tax notification and the top-up tax return. (Members can download our Hong Kong Pillar Two Filing Checklist pdf)

The top-up tax notification is the live workflow today. It is due within six months after the end of the reporting fiscal year and is used to tell the IRD whether group GloBE filing will be effected in Hong Kong or outside Hong Kong, whether local filing will be used in Hong Kong, and which Hong Kong entity will file the top-up tax return where a designated local entity is used.

The top-up tax return is the substantive Pillar Two return. Hong Kong says it must be filed electronically and that it includes the information required in the standardised GloBE Information Return (GIR). The ordinary deadline is 15 months after the last day of the reporting fiscal year, extended to 18 months for the first transition year. A designated local entity can be appointed annually so that one Hong Kong constituent entity files for the Hong Kong group members for that fiscal year.

The IRD’s first phase portal went live on January 19, 2026 for annual notifications. The return-filing module is planned for the fourth quarter of 2026. So the published Hong Kong materials currently give detailed process rules for portal access, authentication, group-code registration and notification filing, but not yet a public phase-2 return user guide or a public XML/XSD package for the top-up tax return.

Hong Kong Requirements 

For an in-scope MNE group, Hong Kong’s current framework requires an annual top-up tax notification plus an annual top-up tax return. The top-up tax return serves both the GloBE rules and the Hong Kong minimum top-up tax (HKMTT), and it also carries the GIR information unless Hong Kong is entitled to receive that GIR information from another jurisdiction under a qualifying competent authority arrangement.

Hong Kong uses the term Part 4AA entity for the persons that come into this system. In the IRD materials this covers Hong Kong constituent entities, Hong Kong standalone JVs, Hong Kong members of a JV group and Part 4AA stateless constituent entities.

A key local simplification is the designated local entity concept. For Hong Kong constituent entities, one Hong Kong constituent entity may be appointed annually to file the top-up tax return and separately the annual top-up tax notification, relieving the other Hong Kong constituent entities of the same group for that fiscal year. Hong Kong standalone JVs and Part 4AA stateless constituent entities, however, do not get the same broad relief and generally need their own notification.

Registration and account access

Hong Kong does not require a separate Pillar Two account registration. The Pillar Two Portal sits inside the Business Tax Portal (BTP). So the starting point is not the Pillar Two Portal itself, but BTP and, if a service provider is involved, the Tax Representative Portal (TRP).

For a corporate filer, the registration path is: an individual first has a BTP user account, the responsible person opens the BTP business account for the entity, and at least one BTP administrator is appointed. BTP administrators can then appoint other administrators and authorised users to handle the relevant online services.

For a service provider, the route is one step longer. The service provider first needs a BTP business account, then a TRP business account, then TRP team setup and client engagement. Once the client is successfully engaged, the relevant TRP team members can access the client’s Pillar Two matters through TRP.

For a non-corporate Part 4AA entity, the person acting for or managing the entity (PRM) has to be reflected in the BTP profile. An individual PRM can access the portal through the entity’s BTP account. A corporate PRM uses the TRP route.

Hong Kong has also created a practical workaround for entities without a Hong Kong business registration number. If the entity is not carrying on business in Hong Kong but still needs BTP access for Pillar Two reporting, it can request a Business Registration Number Equivalent (BRNE) from the IRD by email. That BRNE then performs the same function as a BRN for BTP registration.

Authentication and filing

Hong Kong’s authentication rule is strict: the person who signs and submits a top-up tax notification or top-up tax return must use an e-Cert (Organisational) with AEOI Functions issued by the Hongkong Post Certification Authority. A personal certificate is not accepted. Nor is an ordinary organisational certificate without the AEOI feature.

However, if the organisation already uses an e-Cert (Organisational) with AEOI Functions for country-by-country reporting, that same certificate can also be used for the Pillar Two Portal.

A service provider engaged under Schedule 63 can handle filing matters through the Pillar Two Portal. By contrast, a tax representative who is only appointed as a tax representative and not engaged as a service provider cannot file a top-up tax notification or top-up tax return. That person can view filed material, make enquiries and lodge objections through TRP, but not do the actual filing submission.

Group-code registration: MNE code, JV code, BRN, BRNE and NOTIN