New law amends Pillar Two compliance

On 22 October 2026, the Belgian Parliament adopted a law amending certain Pillar Two compliance requirements introduced by the Belgian Pillar Two Law of 19 December 2023, subsequently updated by the laws of 12 May 2024 and 19 December 2025. The new law introduces four key changes to Belgium’s Pillar Two compliance framework:

• A more detailed penalty framework;

• Clarification of the filing requirements for the income inclusion rule (IIR) and undertaxed profits rule (UTPR), including separate IIR and UTPR returns;

• Alignment of the filing deadline for the qualified domestic minimum top-up tax (QDMTT) return with the GloBE information return (GIR) deadline; and

• Transposition of the EU DAC 9 directive, providing a framework for the exchange of GIRs between EU member states.

The new law was fully enacted on 30 October 2026, when it was published in the Official Gazette.

New penalty framework

The new law introduces more detailed penalty ranges based on the nature of the infringement, with higher penalties applying where fraudulent intent or an intent to cause harm is involved.

A royal decree should specify the exact scales and amounts depending on the severity and recurrence of the infringement.

The law also expressly allows these fines to be waived where there is no bad faith. Where mitigating circumstances exist, the court with jurisdiction over the case may reduce a fine below the statutory minimum. However, the reduced fine cannot be less than 40% of the minimum amount under the applicable penalty scale established by royal decree.

In addition to these fines, the tax authorities may impose tax increases and penalties for insufficient tax prepayments.

Clarification of IIR and UTPR filing obligations

Under the current Belgian Pillar Two legislation, article 57/1 provides for a single tax return covering both the IIR and UTPR. The legislation provides that this return is to be filed by a Belgian group entity or designated local entity.

In practice, however, the Belgian tax authorities have implemented separate IIR and UTPR returns. The IIR return is filed by each parent entity that is subject to the IIR, whereas the UTPR return is filed by the group’s general representative in Belgium. The current administrative filing process therefore differs from the framework contemplated by the existing legislation.

The new law aligns the legislation with this administrative practice and clarifies when an IIR or UTPR return is required. Specifically, the relevant return is required only where Belgium has taxing rights under the IIR or UTPR, irrespective of whether any top-up tax is ultimately payable.

For example, where the group’s ultimate parent entity (UPE) is located in a jurisdiction that applies a qualifying IIR and Belgium therefore has no taxing rights under the UTPR, the group would not be required to file a Belgian UTPR return.

Alignment of the QDMTT return deadline with the GIR filing deadline

Under the current Belgian Pillar Two rules, the QDMTT return is due by the last day of the 11th month following the end of the fiscal year. As a result, the QDMTT return is currently due earlier than the GIR.

The new law aligns the QDMTT return deadline with the GIR filing deadline. Under the new rules, the QDMTT return will be due by:

• The last day of the 15th month following the end of the fiscal year; or

• the last day of the 18th month following the end of a fiscal year that begins no later than 31 December 2024.

The amendment therefore provides multinational enterprise (MNE) groups with additional time to prepare the Belgian QDMTT return and aligns the QDMTT compliance timetable with the GIR timetable.

As a result, the relevant Belgian Pillar Two filings will generally follow the same filing timeline. Depending on the circumstances of the group, Belgian Pillar Two compliance may include the QDMTT return, GIR notification, GIR, general representative declaration, IIR return, and UTPR return.

Implementation of DAC 9 into Belgian law

Finally, the law transposes the EU DAC 9 directive into Belgian law and establishes the framework for the automatic exchange of GIRs between Belgium and other EU member states.

For MNE groups, an important limitation is that DAC 9 provides for the exchange of GIR information within the EU only. It does not provide the legal basis for Belgium to exchange GIR information with non-EU jurisdictions. Such exchanges are addressed separately through the Multilateral Competent Authority Agreement on the Exchange of GloBE Information (GIR MCAA).

Belgium has signed the GIR MCAA, but the domestic ratification process has not yet been completed, and the new law does not itself complete that process. Separately, on 12 October, the Belgian Council of Ministers adopted a draft bill providing for ratification of the relevant multilateral framework. This draft bill is now subject to review by the Council of State before it can be introduced in the Belgian Parliament.

Implications for taxpayers

The alignment of the QDMTT return deadline with the deadlines for other Belgian Pillar Two filings provides MNE groups with additional time to prepare for the FY2025 compliance cycle and simplifies the Belgian compliance process by introducing a common filing timeline for the relevant Pillar Two filings.

In addition, the new law introduces a more detailed and differentiated penalty framework for noncompliance. However, the specific penalty amounts under the applicable ranges will need to be established by royal decree, and no such implementing decree is currently contemplated.

How Deloitte can help

Deloitte can assist MNE groups with all aspects of Pillar Two compliance in Belgium and globally. Deloitte’s Pillar Two Agent technology is designed to support MNE groups with an end-to-end compliance solution. From data collection and validation through tax return preparation and submission, the Pillar Two Agent provides transparency and efficiency through a single cloud-based compliance and reporting technology platform.