For your information, the date of receipt of the declaration by the Administration des Contributions Directes (ACD) is decisive, not the postmark on the envelope.
Filing an income tax return enables tax deducted at source to be adjusted (e.g. salaries, pensions, dividends, etc.), other income to be taken into account (e.g. rental income, self-employed professionals, etc.), and certain expenses to be deducted (e.g. interest owed, insurance, donations, domestic and childcare costs, etc.).
After this date of 31 December 2025, you run the risk of a summons or even compulsory taxation by the ACD.
Of course, we'll be happy to help you with this administrative process, so don't hesitate to contact us!
The Luxconcept team
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