Many people think that an unused or almost empty account does not have to be included in their declaration. This is false. As Service-Public.fr reminds us, article 1649 A of the General Tax Code requires accounts opened, held, used or closed abroad to be declared each year via form 3916 or 3916-bis.“Even if there are 2 euros in the account, you have to declare the account held abroad »recalls Maître Lucie Hamot, tax lawyer. The former expatriate who has kept his current account, the investor who uses a foreign broker, the holder of a crypto account or the child who has become joint owner of an elderly parent’s account are all affected.
Expatriation remains one of the most frequent cases. “I had another case yesterday of an American. I told him: list me all the accounts you have in the United States. He replied: I am unable to list them all.says Master Hamot. “We will have to declare them all. » For the lawyer, these expatriation returns are one of the primary reasons for tax regularization. International successions also create many oversights. An heir may discover Luxembourg life insurance or an old account held by a relative abroad, without knowing that these assets must also be declared, even if they do not generate any immediate income.
Family accounts are the trickiest
The most common trap is not the sophisticated offshore account, but the simple family account. Many become joint holders or obtain power of attorney on the account of a parent who remained abroad, without imagining the reporting obligation.
“We don’t think we’re joint owners”summarizes the lawyer. However, all holders must declare the account, even without using it. She cites the case of a Portuguese family where several members appeared on the same account without having declared it: each was sanctioned.
Same logic for powers of attorney: many sign simply to help an elderly parent manage their expenses or anticipate a health problem, without thinking that this signature could trigger a tax obligation. This is one of the most common cases of regularization among families who have retained property ties abroad.
Revolut, Wise, Trade Republic… and even crypto accounts
Another massive blind spot: neobanks and foreign brokers. Revolut, of Lithuanian origin, N26, German bank, WiseBritish company, or TradeRepublica German broker, made it easy to open accounts outside France.
Many considered them to be simple applications. “People were completely unaware that they had an account abroad”explains Master Hamot. Same logic for crypto accounts opened on certain foreign platforms, which are also subject to declaration.
The first instinct remains to check the IBAN: if the main account does not start with “FR”, you have to ask yourself the question.
A fine that can quickly explode
In the event of non-declaration, the fine is 1,500 euros per account and per non-prescribed year. If taxable income has also escaped the tax authorities, interest, dividends, capital gains, increases may be added, up to 80%.“It’s 1,500 euros per undeclared account per year”insists Maître Hamot. Simple negligence on several accounts can therefore cost several thousand euros, sometimes more than what the account actually earned.
“It is really the inspector who will make the proposal for rectification and it is with him that we will negotiate”she specifies.
Regularize yourself before the check
When a taxpayer discovers an oversight, the best strategy remains spontaneous regularization. It is not enough to declare the account this year: the opening date must be mentioned. The right reflex is to file corrective declarations. “They are often very well received and may not give rise to any sanctions when they are spontaneous”explains Master Hamot. Better to correct before being audited than to wait for a letter from the tax authorities.
A forgotten account often continues to cost far more than it earns.


