The first income tax declaration in France is often a source of confusion for newly arrived foreigners. When do I need to declare? Do I include income earned abroad before my arrival? How is double taxation handled? This guide answers all these questions for 2026.
Are you a French tax resident?
You are a French tax resident if any of the following criteria are met: your home (family) is in France, you carry out your main professional activity there, or your main economic interests are there. As a French tax resident, you must declare all your worldwide income, including income earned abroad.
What to declare in your first return
For a first return, include: income earned in France from the date of your arrival (not before), income from foreign sources if you were already a tax resident on 1 January of the relevant tax year, and foreign capital income. If you arrived mid-year, you only declare income for the period of tax residency.
Double taxation: how to avoid paying twice
France has signed tax treaties with over 120 countries to avoid double taxation. For foreign-source income, a tax credit or exemption may apply under the applicable treaty. Check the bilateral convention for your country of origin on the DGFiP website. FrenchDesk can help you draft an enquiry letter to the relevant SIE.
If you missed the declaration deadline
2026 deadlines for 2025 income: mid-May for paper returns, end of May-June depending on the département for online returns. Late filing attracts a 10% surcharge. If you are acting in good faith, you can request a waiver by letter to the SIE. FrenchDesk generates this letter in 30 seconds.