Your research activities in France and your stay in the country may, depending on your circumstances, give rise to tax obligations.
Espace Ulys has created a guide to help you better understand your situation, how to contact the tax authorities, and the main steps to take.

This guide provides general information. If your situation is more complex, we recommend that you contact your local Individual Tax Office (SIP) or a tax advisor.

Upon arrival in France

If you have an employment contract in France, income tax will be deducted directly from your salary. It may be a good idea to request that your personal at-source income tax rate be personalized: To do this, you must fill in form 2043-SD, in paper format for your first application, or online if you already have a personal account on the tax authority website. Check out our Tax Guide for more information and the video on how to complete your first tax return.

In all cases, you must also determine whether you are a tax resident in France or not. If you are a tax resident, you must file a tax return in France for any income earned in France and from abroad. If you are not a tax resident, you only declare income earned in France.

The year following your arrival

If you have an employment contract in France, income tax is generally deducted directly from your salary at the source. Referencing form 2043-SD has become too specific and is no longer the general procedure highlighted by the tax authorities. Procedures change regularly; it is preferable to refer to the general procedure for personalizing the tax rate.
It is also essential to determine whether you are a tax resident of France under tax legislation and, where applicable, the tax treaty between France and your country. If you are a tax resident, you must declare all your worldwide income (both French and foreign) in France. If you are a non-resident, you must declare only your income sourced in France.

In 2026, you will have to declare your income received in 2025. The tax return campaign begins on April 9, 2026 and ends between the end of May and the beginning of June depending on your department.

When leaving France

Before you leave, it is important to determine whether or not you will remain a tax resident of France, as this can affect your tax obligations.

You must also notify the tax authorities of your new address so that you continue to receive information regarding your file.