In France, income tax is calculated at the tax household level, which groups the income and expenses of all household members. A tax household can include multiple individuals, and in some cases, unrelated people. Married couples or civil union partners can choose between joint or individual declarations, which affects the overall tax calculation.

When a tax return is filed, it must be filed by tax household, not by individual. This means that all persons in the tax household must be included in the tax return, and their income and expenses must be taken into account for the calculation of income tax.

💡 Note that in the case of a married or civil union couple, they can choose to make a joint or individual declaration.

If the joint declaration is chosen, the income and expenses of each member of the couple will be combined to form a single tax household. If the individual tax return is chosen, each member of the couple will constitute their own tax household.

Simple point, the tax return is made by tax household in France, and this allows to take into account the income and expenses of all the people who compose this household for the calculation of the income tax.

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