You can find a detailed overview of the French tax system in the online brochure published by the DIRECTION GÉNÉRALE DES FINANCES PUBLIQUE.

Every year, if you are considered a French resident for tax purposes, you must declare your income in order to establish the amount of your next tax notice.

Income tax

You must declare your income to a French institution the preceding year (N-1) to the declaration. The declaration is mandatory, even if the income is not taxable. In general, the declaration must be made online in April. Your spouse must also declare income, even if he/she no longer lives with you.

Tax withholding - Prélèvement à la source

From January 1st, 2019, taxes will be "prélevées à la source". That means that your income tax on your salary will be withheld from your salary every month to make it easier for you. You can adjust the amount of taxes you pay every month should your personal situation change during the year (you lose your job, get a salary raise…). The amount of taxes you’ll pay will not communicated to the employer, because the tax administration sets the tax rate according to the declared income (salaries, legacy, etc.). However, it is still necessary to prepare an income tax return each following year to determine the actual amount of taxes you owe and include potential tax deductions (e.g. donation to an association, child care tax credits for children under 6 years old etc.). More information on the tax withholding.

If you receive or will receive a salary and you do not yet have a French fiscal number, you can request a fiscal number and obtain a personalized withholding tax rate using this form or via email. The French fiscal number allows you to submit your income tax return online and to request an adjustment of the withholding tax rate.

If this is your first declaration and you do not have a French tax number yet, you need to send in a hardcopy tax declaration. To obtain the declaration form, one must go to the public finances center closest to one’s domicile (Here is the list of centers in Nice) or download the form.

The form comes with an explanatory guide. The form will then need to be returned or by postal mail. We recommend you send your tax delcaration by registered mail and keep a copy for your personal records.

If you have difficulties in completing the form, agents at the tax office can help but they will require relevant documents to validate the information (for example: pay checks... etc.)

You can find more information on income tax issues specific for foreigners here and here.

The habitation tax

If you occupy a dwelling on January 1, you must pay a habitation tax which is evaluated relative to your income, but also in terms of the characteristics of the dwelling. Whether you stay in France or not, the tax must be paid. The tax bill usually arrives in September or October at the place of residence or at the last declared address.

And bilateral fiscal conventions?

Certain countries have bilateral fiscal conventions with France. This aims to avoid double taxation. Some conventions even provide exemptions for scientists. Each convention is different. You can consult this site to verify if your previous country of residence for tax purposes and France have a bilateral fiscal convention and, if so, complete the process indicated on the site. Otherwise, you can print the convention and seek the advice of the public finance center closest to your residence on how to best proceed.