How to Become a French Citizen in 2026: Every Route for UK and US Applicants

Which route to French citizenship fits you?

The right route depends on your family, your marriage and where you live. This table compares the four main routes for people applying from the UK or the US.

Not sure which route fits you? Get a free eligibility check

How does French citizenship by descent work?

If one of your parents was French when you were born, you are usually French from birth, wherever you were born. You don't apply to become French: you prove it with a Certificate of French Nationality (CNF), then use it to get a French passport.

• Where to apply: if you were born and live abroad, send the request to the French Nationality Service of the Paris court (Tribunal judiciaire de Paris), by post or in person.
• Form and cost: cerfa 16237. It's free.
• Time: the court has 6 months from your receipt, extendable twice. If it doesn't answer by the final deadline, the request counts as refused.
• If refused: you have 6 months to challenge it in court, and a lawyer is mandatory.
• The 50-year rule: if your family has lived abroad for more than 50 years and neither you nor your French parent ever had French documents, such as a passport or ID card, French courts may refuse to hear the claim. Check this before paying for records.

Going back to a grandparent is possible when nationality passed down every link of the chain, and each link has to be proven with civil records. Read our full guide to French citizenship by descent.

Official source: Service-Public – Certificate of French nationality

How do you get French citizenship by marriage?

If you are married to a French citizen, you can become French by declaration after 4 years of marriage, instead of going through naturalisation.

• Marriage length: 4 years. It's 5 years if you have lived in France for less than 3 years in total and your spouse was not registered with a French consulate while you lived abroad.
• Shared life: you must have lived together continuously since the wedding, and your spouse must have been French throughout.
• French: B2 since 1 January 2026, proven by a diploma or an approved test.
• Where: from the UK or US, at the French consulate; in France, at your local naturalisation platform. Both spouses attend an interview.
• Fee: €255.
• Time: the ministry has 1 year from the interview receipt to refuse registration.

A marriage held abroad must first be transcribed into the French civil registers.

Official source: Service-Public – Nationality by marriage

How does naturalisation work after 5 years in France?

Naturalisation is for people who have built their life in France, usually after 5 years of residence. Unlike descent, it is not a right: the French state decides based on your whole situation.

• Residence: usually 5 years. It drops to 2 years if you earned a French higher-education diploma after 2 years of study, and other exceptions exist.
• You must live in France when the decree is signed. Applying from the UK or US is only possible in narrow cases, such as working for the French state.
• French: B2, written and oral, since 1 January 2026.
• Civic exam: 40 multiple-choice questions on five themes; you need 32 correct answers to pass.
• Also checked: stable income, no serious criminal record, age 18 or over, and an interview on French values.
• How: online, through the official naturalisation service. Fee €255.
• Time: up to 18 months from your receipt, or 12 months if you have lived in France for 10 years or more.

Most British and American applicants reach naturalisation after starting on a long-stay visa, a Talent Passport or the entrepreneur route. See our guide to the 2026 naturalisation rules.

Official source: Service-Public – Naturalisation by decree

Are there other ways to become French?

• Parent or grandparent of a French citizen: if you are 65 or over, have lived in France for 25 years and have a French child, grandchild or great-grandchild, you can declare French nationality. There's no language test. Fee €255. Official source.
• Born in France, reintegration and other special cases: these have their own rules. We check them on the free call.

What changes if you're British or American?

If you're British

• Why it matters since Brexit: a French passport gives you back EU free movement, so you can live and work anywhere in the EU without a visa or the 90/180-day limit.
• You keep your British citizenship. The UK government does not object to its citizens holding other nationalities (GOV.UK).
• Descent claims go by post to the Paris court; you don't need to travel.
• Marriage declarations are filed at the French consulate if you live in the UK.
• Naturalisation needs 5 years living in France, so it usually starts with a long-stay visa.

If you're American

• You keep your US citizenship. The State Department says a US citizen may naturalise in a foreign state without any risk to their US citizenship (travel.state.gov).
• One rule to know: you must still enter and leave the United States on your US passport.
• Descent claims go by post to the Paris court, wherever you live in the US.
• Marriage declarations are filed at the French consulate that covers your state.
• Naturalisation also needs 5 years living in France, usually after a long-stay visa or a Talent Passport.

Documents: what usually slows people down

• Birth and marriage certificates for every link in the chain (descent) or for both spouses (marriage).
• Foreign documents usually need an apostille and a sworn French translation.
• Older records for parents and grandparents can take months to obtain, so order them first.

What are the most common mistakes?

1. Applying for the wrong route. People with a French parent apply for naturalisation, when they may already be French by descent and need only a CNF.
2. Missing the 50-year rule. Families settled abroad for generations spend money on records before checking whether the claim can be heard at all.
3. Filing without B2 proof. Since 1 January 2026, marriage and naturalisation files need a valid B2 diploma or test result.
4. Assuming silence means "still processing". For a CNF, no answer by the final deadline counts as a refusal, and the 6-month challenge period starts running.

Check your route with a lawyer before you spend: free call