2026 Taxes: the starting gun fires on April 9th, with couples and savers targeted by new measures.

This Thursday, April 9th, marks the start of the 2026 income tax filing season, with a distinctly French ritual: check, correct, validate, and then wait for the final adjustment. This concerns income earned in 2025, under a withholding tax system implemented since 2019, designed to closely reflect salary fluctuations and changes in family circumstances. On paper, everything is supposed to be smoother. In reality, however, a single misunderstood detail can quickly lead to a hefty tax bill.

The couple at the individualized rate, without thinking about it

A significant change this year for married or civilly partnered couples: starting in September 2025, the individualized tax rate will apply by default, in accordance with the 2024 Finance Law, unless another method is explicitly chosen when filing their tax return. In practical terms, each partner will have a rate deducted based on their own income. The total household tax amount remains the same; it's the allocation that changes, which can be significant when incomes are very unequal. Many will see this as a measure to improve transparency, while others will see it as just another little mechanism to keep an eye on, because automatic processes have a knack for lulling us into complacency.

Another, more discreet but very real change: the income tax scale has been increased by 0,9% to account for inflation, with brackets ranging from 0% to 45% depending on the family quotient, determined by the household composition. And on the capital gains front, the situation is getting more favorable: the flat tax is rising to 31,4% instead of 30%, applied by default to dividends, interest, and other investment income. The government explains this increase by the rise in the CSG (General Social Contribution) since January 1, 2026. Between adjustments to tax brackets and a cut to savings, the tax season begins, as is often the case, with a simple reminder: taxes don't take a vacation, and the trajectory of levies is determined over several years.