Belgium has published Royal Decrees (5 June 2026) in Official Gazette No. 129 establishing return forms for both the Qualified Domestic Minimum Top-Up Tax (QDMTT) and the Income Inclusion Rule (IIR) applicable to the 2025 assessment year.
Belgium’s Ministry of Finance has gazetted Royal Decrees establishing the return forms for both the Qualified Domestic Minimum Top-Up Tax (QDMTT) and the Income Inclusion Rule (IIR) for the 2025 assessment year. Both Royal Decrees of 5 June 2026 include an attached form as an annex and are published in the Official Gazette No. 129 of 15 June 2026.
Qualified Domestic Minimum Top-Up Tax (QDMTT) return form
The form includes detailed information on Belgian companies subject to the QDMTT, the filing entity, and the group’s consolidated structure and accounts. It also requires data on Belgian group entities, joint ventures, and excluded entities, as well as jurisdictional safe harbour and de minimis information. In addition, it covers group tax options, calculations of the applicable QDMTT rate and liability, advance payments and related increases, and contact details.
Income Inclusion Rule (IIR) return form
The form includes identification details for companies subject to Belgium’s IIR, the filing entity and group (including multinational and large domestic groups), consolidated group accounts, and calculations of the IIR top-up tax. It also covers information on relevant paying entities, group and joint venture structures, advance payments, the final tax amount, and designated contact persons.
The form comprises five structured sections. The first captures taxpayer and group identification, including fiscal ID numbers, group names, Pillar Two identification numbers, and consolidated account details. The second section calculates top-up tax for both the entity itself and other group members. The third addresses Pillar Two advance payments by quarter. The fourth determines final tax liability, accounting for increases on insufficient advance payments. The fifth requires contact person details and authorised signature certification.
Taxpayers must provide complete information in both the presentation currency and euros for accurate compliance assessment.
Both of these forms are required for companies subject to the minimum tax introduced by the Law of 19 December 2023, which applies to multinational enterprise (MNE) groups and large-scale domestic groups
