Before you start

A French tax number, issued after your first declaration
Records of worldwide income for the year
A French bank RIB
Credentials for impots.gouv.fr, once you have a number

Step-by-step

1
Fix the withholding rate on your first payslips
With no French tax history, your employer applies the taux neutre from a published grid based on your salary alone. It ignores your household, your children and any other income. Once you have a tax number you can request a personalised rate through impots.gouv.fr, and you can modulate it when your circumstances change. Do this rather than waiting a year for the reconciliation.
OnlineWho: YouAs soon as you have a tax number
2
Understand that withholding does not replace the declaration
Prélèvement à la source deducts tax from your salary, but the annual declaration in the spring is still mandatory. It reconciles the withholding, applies the household quotient and reliefs, and captures income the withholding never saw.
OnlineWho: YouSpring annually
3
File your first declaration on paper if you have no tax number yet
The online service needs a tax number you do not receive until you have filed once, so the first declaration usually goes on paper to your local tax office. This circularity catches everyone and the office is entirely used to it — ask them directly.
In personWho: You
4
Work out your parts and what the quotient does for your household
A single person counts as one part, a married or PACSed couple as two, with additional half-parts for children. Income is divided by the parts, taxed on the scale and multiplied back. The reduction is substantial for a couple with unequal incomes and for families.
OnlineWho: You
5
Get the actual taxe foncière bill before you make an offer on anything
Grenoble's rate on built property is the highest among France's fifty largest communes and roughly triple Paris's, following a 25% increase to the municipal share voted in early 2023. A national average or a comparison with another French city will understate it badly. Ask the seller for their last avis de taxe foncière rather than estimating.
OnlineWho: You
6
Declare every foreign account — the penalty is fixed and it is applied
French tax residents must list all foreign bank accounts, life insurance contracts and digital asset accounts annually, whether or not they generated income. The account people forget is almost always a dormant one at home.
OnlineWho: You

Documents you’ll need

French tax number, once issued
Payslips and the annual employer summary
Records of all foreign income and foreign accounts
RIB for refunds and payments
Marriage or PACS documentation, for household parts

Things most newcomers don’t know

Grenoble has the highest local property tax of any large French city, by a wide margin and on purpose.

The national landlords' observatory put Grenoble top of France's fifty largest communes in October 2025, on a global rate close to 68% — roughly triple Paris's — after the municipality voted a 25% increase to its share in early 2023 and defended it as a deliberate budget choice. Tenants pay none of this, so it is irrelevant to renting. For anyone converting a rent-versus-buy calculation from abroad, or comparing Grenoble against Lyon or Nantes on carrying cost, it is the single largest local variable and it is invisible in a sale price.

Source: impots.gouv.fr / Observatoire national des taxes foncières

The rate on your first French payslip is a guess, and you can correct it in ten minutes.

With no filing history, prélèvement à la source falls back to the taux neutre — a published grid keyed to salary alone that knows nothing about your spouse, your children or your other income. For a single earner supporting a family it is usually far too high; for two earners it can be too low, storing up a bill. Once you have a tax number you can request a personalised rate online and it applies within a couple of months. Most newcomers never realise the number was provisional.

Source: impots.gouv.fr

A ski flat kept as a second home is taxed as a policy instrument, not an oversight.

Taxe d'habitation was abolished on principal residences but retained on second homes, and communes in pressured housing areas may add a surcharge of up to 60% on the commune's share. Grenoble voted the maximum in September 2021, applying from 2022, and mountain communes across the Isère have their own positions. Anyone tempted by a small place up a valley should check that specific commune's rate before, not after.

Source: service-public.fr

France taxes the household, which changes the answer completely depending on who you are.

The quotient familial divides household income by a number of parts before applying the scale — one for a single person, two for a married or PACSed couple, extra half-parts for children. A couple with one high and one low income pays substantially less than two individuals earning the same amounts; a single high earner does comparatively badly. Comparing French tax against a country with individual taxation is meaningless without specifying the household.

Source: impots.gouv.fr

Common mistakes to avoid

Budgeting a property purchase here on a national-average taxe foncière figure.
Accepting the taux neutre on your payslip as though it were your actual tax rate.
Assuming withholding at source removes the obligation to file annually.
Buying a mountain second home without checking that commune's residence-tax surcharge.
Failing to declare a dormant foreign bank account and incurring the fixed per-account penalty.

Some of this may be out of date. Spotted something inaccurate? Help us keep it right for the next newcomer.