Summary (3
- Belgium has postponed the filing deadlines for both the Domestic Top‑up Tax (QDMTT / domestic surcharge) and the Income Inclusion Rule (IIR) surcharge under its Pillar Two regime. [finance.belgium.be]
- The postponement applies to the first wave of Pillar Two filings, acknowledging practical and technical constraints faced by in-scope groups. [finance.belgium.be]
- The measure is intended to align Belgian compliance timelines with international Pillar Two reporting, notably the OECD GloBE Information Return (GIR). [finance.belgium.be]
Article
The Belgian Ministry of Finance has officially announced a postponement of the filing deadlines for certain tax returns required under the Belgian implementation of the OECD/G20 Pillar Two minimum taxation framework. The deferral concerns both the domestic top‑up tax return (Qualified Domestic Minimum Top‑up Tax – QDMTT, referred to in Belgian law as the “binnenlandse bijheffing”) and the Income Inclusion Rule (IIR) top‑up tax return. [finance.belgium.be]
This decision forms part of Belgium’s broader administrative approach to the initial implementation phase of Pillar Two, which introduces a 15% global minimum effective tax rate for multinational enterprise (MNE) groups and large domestic groups falling within scope. The Belgian authorities explicitly refer to the complexity of the new compliance obligations and the need to ensure that taxpayers have sufficient time to prepare accurate and technically robust filings. [finance.belgium.be]
Under the original rules, in-scope taxpayers were required to submit their Belgian Pillar Two returns within 11 months following the end of the financial reporting year, potentially triggering first filings as early as late 2025 for calendar-year groups. By granting a filing delay, the Ministry of Finance aims to reduce immediate compliance pressure, particularly in light of evolving administrative guidance, technical filing specifications and the interaction with OECD-level reporting requirements such as the GloBE Information Return (GIR). [finance.belgium.be]
The postponement applies specifically to:
- the domestic top‑up tax return, which ensures that low-taxed Belgian profits are brought up to the minimum effective tax rate through a qualified domestic mechanism; and
- the IIR top‑up tax return, under which a Belgian parent entity may be required to pay top‑up tax in respect of low‑taxed income of foreign group entities.
From a practical perspective, this measure provides welcome additional time for tax and finance teams to finalise Pillar Two data collection, system adaptations, modelling, and internal governance processes. It also reinforces Belgium’s intention to maintain consistency with international Pillar Two developments and to avoid mismatches between local and global reporting timelines. [finance.belgium.be]
Taxpayers falling within the scope of the Belgian Pillar Two rules are nevertheless advised to continue their preparation efforts without delay, as the postponement does not alter the substantive tax obligations, nor does it remove potential penalties for non-compliance once the new deadlines apply. Further technical details and practical filing instructions are expected to be published via the Belgian tax administration’s dedicated Pillar Two portal. [finance.belgium.be]
Source: Belgian Ministry of Finance – Pillar Two updates (FPS Finance)
Belgium – Pillar Two (official page)
