Belgium has enacted legislation transposing Directive (EU) 2025/872, extending the filing deadline for the supplementary national tax return to 15 months after the fiscal year-end, with an 18-month transitional period for earlier fiscal years.
Belgium’s Federal Public Service (FPS) Finance, in a release on 30 October 2026, has confirmed a change to the standard filing deadline for top-up tax returns under its qualified domestic minimum top-up tax (QDMTT) rules.
The deadline is now the last day of the 15th month following the end of the fiscal year. A transitional extension applies to fiscal years beginning on or before 31 December 2024, allowing filing by the last day of the 18th month following the fiscal year-end.
For example, the deadline for a fiscal year running from 1 January to 31 December 2025 is 31 March 2027. Under the previous rules, the deadline would have been 30 November 2026.
The change follows the publication of the Law of 25 October 2026 implementing Council Directive (EU) 2025/872 (DAC9) in the Belgian Official Gazette on 30 October 2026.
