The French tax declaration season is now open, but how much do you really need to tell the French taxman about your affairs outside of France? International tax specialist Jason Porter explains some essential information.
Tax declarations
Every year, anyone who is resident in France (and some non-residents) must fill out the annual tax declaration. Declarations are now open for 2026 – covering your income from 2025.
If you live in France, it’s almost certain that the tax declaration will be compulsory for you, and if you are non-resident but you have income in France (for example rental income from a French property) you will also need to fill out the declaration.
It’s important to note that if you live in France but all your income comes from abroad (eg a UK or US pension), you still need to fill out the declaration. Find the full details HERE.
But the French tax form only covers my income in France, right?
Wrong. This is the source of much confusion to foreigners in France, but actually you need to tell the French taxman about all your income.
Most jurisdictions operate on the basis that if you are resident, then you declare your worldwide income, and if you are not resident you only declare the income which is actually sourced in that jurisdiction. But then you could end up paying tax twice – eg in the UK and France – on the same income.
Double Tax Treaties between two states are designed to eliminate this possibility.
The exact treaties vary depending on the country the income comes from, but most operate on the basic premise that people shouldn’t have to pay tax twice on the same income. In most cases, this is achieved through tax credits.
As an example, tax paid in the UK on UK rental income is available as a tax credit against the French tax liability on the same income.
Many foreigners in France believe that if they have already declared – and paid tax on – income in the original country, then they don’t need to declare it again in France.
This is not the case – all non-French income still needs to be declared on a French tax return.
The commonest areas of non-declaration for Brits are around UK source rental income, UK bank interest and other UK investment income (dividends, etc., from shares and securities in companies and funds).
In particular, ISAs are commonly missed off French tax returns. Whilst they have tax efficient status in the UK, in France you would “look through” the ISA vehicle, and declare the underlying dividends, interest and capital gains on your French tax return.
What about bank accounts at home?
The French government has recently taken steps to further strengthen its fight against tax fraud, extending the disclosure regulations to also cover non-active bank accounts.
You must now declare all non-French bank accounts and life insurance policies, even if you have not deposited any funds, earned any interest/gains or made any withdrawals. The penalties for failing to declare a foreign account are the same whether it is active or not (and these can be substantial).
This has now become even more real with the CRS (Common Reporting Standards) exchange of financial information between states.
Fines can be levied for non-declaration of foreign bank accounts – up to a maximum of €10,000 per account.
READ ALSO: Do I need to declare my foreign bank accounts to French taxman?✎
When do I need to pay up by?
Tax declarations opened online earlier in April with the deadlines varying depending on where you live in France.
READ ALSO: French tax deadlines in May and June 2026✎
Any balance of tax due must be settled by the end of the year (penalties will apply for non-payment). Or, where applicable, the tax authorities will refund any overpayment.
If you are an employee and you’ve already had your income taxed at source, you might actually get money back from the taxman if you qualify for any tax breaks or rebates – more details on those here.
For more information on the French tax declaration, how to fill in the form and where to find professional help if you need it, head to our tax section HERE.
