DAC9 Transposition and New DTT Return Deadline

The Belgian government has submitted a draft law to Parliament to transpose DAC9 into Belgian legislation and to introduce further amendments to the Belgian law on minimum taxation. Most notably, the filing deadline for the domestic top-up tax return (DTT return) will be aligned with the filing deadlines of the other Pillar Two returns.

The draft law is expected to be adopted in the coming months and will enter into force on the date of its publication in the Belgian Official Gazette.

The draft law will transpose into Belgian domestic law the new rules on the automatic exchange of GloBE information under DAC9 (Council Directive (EU) 2025/872). These rules are intended to facilitate the central filing of the top-up tax information return (equivalent to the GloBE Information Return (GIR)) among EU Member States.

The specific rules on the exchange of information with third countries outside the European Union are governed by the Multilateral Competent Authority Agreement on the Exchange of GloBE Information (GIR MCAA).

Since the above rules on the exchange of information have not yet been adopted, the Belgian tax authorities have previously announced their commitment to enabling central filing in line with the OECD announcement of 18 May 2026 (see Pillar 2 compliance formalities in Belgium).

Under the current rules of the Belgian Law on minimum taxation, the deadline for filing the DTT return is the last day of the 11th month following the end of the fiscal year. However, the first filing deadlines of the DTT return were extended, through successive administrative tolerances, to 30 September 2026 (see: Extended deadline for DMTT return and IIR top-up tax return filing).

The draft law will align the filing deadline of the DTT return with the filing deadlines of the other Pillar Two returns. Accordingly, the DTT return deadline will be the last day of the 15th month following the closure of the fiscal year, but the first filing deadline is extended to the last day of the 18th month following the fiscal year that begins by the latest on 31 December 2024. For fiscal year 2025 ending on 31 December 2025, this means that the deadline for filing the DTT return will be 31 March 2027. Furthermore, the new rules may also have impact for groups whose first fiscal year ends as from April 2025. For example, in the case of a first fiscal year running from 1 May 2024 to 30 April 2025, the new filing deadline will be 31 October 2026 (instead of 30 September 2026).

Under the current rules, the upcoming first filing deadline for fiscal year 2025 is 30 November 2026. Although it is not certain that the draft law will be adopted by Parliament in time before this deadline, it is expected that the tax administration will already apply the new deadline, if necessary through administrative tolerance. 

The draft law includes the following further amendments:

• It clarifies that separate filing requirements apply for the IIR top-up tax and the UTPR top-up tax. For the IIR top-up tax, each Belgian entity subject to the IIR top-up tax must submit an IIR return. For the UTPR top-up tax, the Belgian entity subject to the UTPR top-up tax or, where there is more than one such entity, the general representative must submit a UTPR return.
• It adjusts the rules on the general representative. These adjustments are aligned with the implementation of these rules as elaborated in the FAQ published by the Belgian tax authorities (see: Opening portal for top-up tax return submissions in Belgium).

If you require assistance with the Belgian minimum tax or have questions about the applicable rules and their implications for your business, please do not hesitate to contact your trusted KPMG advisor or reach out to us directly.

KPMG can assist you with all compliance aspects of the global minimum tax in Belgium and globally, including registration, calculation of tax liabilities, and filing of the required returns. In addition, we can help you identify the relevant data points, collect the necessary data, and perform the calculations for all top-up taxes.