Belgian Tax Authorities publish Pillar Two Circular Letter

I. Overview

On 22 October 2025, the Belgian Tax Authorities published Circular Letter 2025/C/68 (the “Circular Letter”) providing administrative guidance on the Belgian implementation of the EU Directive 2022/2523 on minimum taxation for multinational enterprises and large domestic groups also referred to as Pillar Two. As a reminder, the Pillar Two rules were introduced in Belgian domestic law through the Law of 19 December 2023¹ as amended by the Law of 12 May 2024². 
 

II. Discussion

In essence, the Circular Letter is based on the OECD’s “Consolidated Commentary to the Global Anti-Base Erosion Model Rules” and “Tax Challenges Arising from the Digitalisation of the Economy – Global Anti-Base Erosion Model Rules (Pillar Two) Examples” as published on 25 April 2024, as well as the EU's “Frequently Asked Questions on Pillar 2 Directive”. The Circular Letter thus does not take into account the latest OECD Agreed Administrative Guidance as published on 17 June 2024 and 15 January 2025.

The Circular Letter is essentially a translation of the OECD commentaries into Dutch and French and does not really include a lot of new additions or insights with respect to tax technical matters. Some of the guidance and examples as included in the preparatory works of the Law of 19 December 2023, have been transposed to the Circular Letter, such as for example how taxpayers can split and allocate a Qualified Domestic Top-up Tax liability in case there are multiple Belgian taxpayers.

The EU Directive 2022/2523 and domestic law deviate on a few points from the OECD Pillar Two rules. In such cases, the Circular Letter confirms that only the Belgian law and the European Directive are applicable.

No reference is made in the Circular Letter to the draft bill introducing certain technical amendments to the Belgian Pillar Two legislation as published on 9 October 2025³. This results in the fact that the Circular Letter sometimes discusses specific tax provisions which the aforementioned draft bill aims to amend or even abolishes.

Chapter 11 of the Law of 19 December 2023, dealing with the assessment and collection of the Pillar Two taxes, is explicitly not addressed in the Circular Letter. In this respect, in-scope Pillar Two taxpayers are obliged to prepare and file a Qualified Domestic Top-up Tax (“QDMTT”) return 11 months following the fiscal reporting year-end and thus, in principle, the first time by 30 November 2025 for calendar year taxpayers. However, the Belgian Tax Authorities have granted a general extension for all QDMTT returns whose statutory filing deadline falls before 30 June 2026, till 30 June 2026.⁴ Practical guidelines and technical documentation regarding the Pillar Two procedure will be communicated at a later date.

The Circular Letter can be accessed on the website of the Belgian Tax Authorities:

Dutch : MyMinfin

French : MyMinfin

In case you need any assistance with the completion of your obligations under the Belgian Pillar Two legislation or more in general with Pillar Two related questions, please do not hesitate to reach out to us or to your dedicated person of contact.

¹ Belgian parliament approves draft bill on Pillar Two | EY - Belgium

² Belgian Pillar Two legislation further aligned with OECD’s guidance | EY - Belgium

³ Belgium proposes technical amendments to its Pillar Two legislation | EY - Belgium

⁴ Belgian QDMTT return deadline extended till 30 June 2026 | EY - Belgium