French nationality by marriage: declaration, deadlines, opposition

If you are married to a French national, you can become French without going through naturalisation. French nationality by marriage rests on a declaration, in other words on a right, not on a favour from the State. It is still closely supervised: length of marriage, a genuine shared life, language level and checks by the authorities. A lawyer reviews your file in 20 minutes on Avocat20min.fr.

French nationality by marriage: the statutory conditions

Everything starts with article 21-2 of the Civil Code. The foreign spouse may make a declaration after four years of marriage. For French nationality by marriage, this period is counted on the filing date.

Several conditions must then all be met:

• A shared emotional and material life, without interruption since the wedding.
• A spouse who stayed French: they must have held French nationality on the wedding day and kept it since.
• A registered marriage: a wedding celebrated abroad must be transcribed in the French civil registers.
• Sufficient knowledge of French, at the level set by decree.
• Lawful residence in France at the time of filing, except for EU, EEA and Swiss nationals.

Finally, some convictions close the door. A sentence of at least six months' immediate imprisonment, or a conviction for terrorism, blocks French nationality by marriage (article 21-27). An expulsion order still in force has the same effect.

Four or five years of marriage?

The four-year period rises to five years in two situations. The first concerns a spouse who cannot show three years of continuous, lawful residence in France since the wedding. The second concerns a couple who lived abroad when the French spouse was not on the register of French nationals living outside France.

In practice, the official guidance reads these two cases together. So a couple settled in France for three years stays at four years. Likewise, an expatriate couple keeps four years if the French spouse had registered with the consulate. Without enough residence in France and without consular registration, however, you must wait five years. The table sums up the rules on French nationality by marriage in 2026.

Couple's situation	Length of marriage required
At least 3 years of continuous residence in France since the wedding	4 years
Living abroad, French spouse on the consular register	4 years
Living abroad, not on the register	5 years
Level of French, declaration made since 1 January 2026	B2 (B1 before)
Tax stamp, file lodged since 1 May 2026	€255

Level B2 French and a €255 stamp since 2026

Two recent changes weigh on French nationality by marriage. First, the decree of 15 July 2025 raised the language level. For a declaration made since 1 January 2026, you must prove level B2, both spoken and written.

You prove this level with a diploma taught in French, or a TCF or TEF test less than two years old. Be careful: a file lodged incomplete in 2025 and completed in 2026 falls under the new rules. On the other hand, this route requires no civic exam, unlike French naturalisation.

Next, the stamp duty went up. It costs €255 for a file lodged since 1 May 2026, against €55 before. You pay it with an electronic tax stamp in France, and at the consulate from abroad.

Filing, the interview and the enquiry

In France, you lodge the declaration with the nationality platform covering your home. Depending on the platform, you file in person or by registered post. If you live abroad, the French consulate receives the file.

Gather your civil status documents, the marriage certificate, proof of your spouse's nationality and your language certificate. For French nationality by marriage, add proof of your shared life too: joint lease, joint tax notice, joint accounts, children together. For your spouse's nationality, a French nationality certificate often makes things easier.

The platform then invites you, normally with your spouse, to an interview. The officer checks your French, your shared life and your commitment to the values of the Republic. A police or gendarmerie enquiry often completes the file. At the end of the interview, you receive a receipt: it starts the deadlines running.

The one-year deadline and refusal to register

The authorities have one year from the receipt to refuse registration (article 26-3). The period rises to two years when opposition proceedings have begun. Without a refusal within that time, the declaration must be registered.

If all goes well, French nationality by marriage takes effect on the date you made the declaration. You then receive a copy bearing the registration endorsement.

A refusal to register, by contrast, must state its reasons. You challenge it before the tribunal judiciaire for your home, within six months of notification. Representation by a lawyer is compulsory. The judge then reviews each condition, for example whether your shared life is real.

Government opposition within two years

Even with a compliant file, French nationality by marriage can still fail. Article 21-4 allows the Government to oppose it by a decree issued after consulting the Conseil d'État. There are only two grounds: unworthiness, or a lack of assimilation other than linguistic.

The decree must come within two years of the receipt. The law treats actual polygamy as a lack of assimilation in itself. The same goes for a conviction for violence causing mutilation or permanent disability to a child under fifteen. Words or conduct contrary to equality between women and men, or to secularism, can also ground an opposition.

You can challenge the decree before the Conseil d'État within two months, with a lawyer. Once the opposition becomes final, you are deemed never to have acquired French nationality.

After registration: fraud and deprivation

Registration does not close the matter. The public prosecutor can challenge French nationality by marriage obtained through lies or fraud (article 26-4). They have two years from the discovery of the fraud.

Above all, if the shared life ends within twelve months of registration, fraud is presumed. You can rebut this presumption, for example by proving an unforeseeable breakdown or domestic violence. So keep your proof of shared life well after registration.

Finally, like anyone who acquired French nationality, you remain exposed for ten years, or fifteen, to deprivation of French nationality. It requires a serious conviction, terrorism in particular, and another nationality.

French nationality by marriage or a resident card?

The two steps do not exclude each other. After three years of marriage, the spouse of a French national may seek a ten-year resident card, subject to conditions. It secures your stay while the declaration is pending.

A separation, however, changes everything. It closes the route to French nationality by marriage and weakens your residence permit. Our article on separation and the spouse of a French national permit sets out your options.

When to consult a lawyer

A lawyer first helps you choose the right moment to claim French nationality by marriage. For example, filing at three years and eleven months of marriage leads to a certain refusal. Likewise, a couple living apart for work reasons must document their shared life.

Then an immigration lawyer prepares the interview, answers an opposition and takes your appeal to the tribunal judiciaire. The official conditions appear on the service-public page on declaration by marriage.