Dual citizenship in France: rules and costs

Key takeaways

Question	Short answer	Why it matters
Does France allow dual citizenship?	Yes, in general France allows multiple nationalities.	France usually does not force you to renounce your original nationality when you become French.
What are the main routes?	Birth or childhood route, descent, marriage, and naturalisation.	Your eligibility depends on the route, not on dual citizenship as a separate application.
Do I still need to check my other country’s law?	Yes, always.	France’s position does not override restrictions in your other country.
What documents are usually needed?	Identity, civil-status records, proof of residence, nationality evidence, and often French translations.	Most delays happen because files are incomplete or records do not match.
How long does it take?	It varies by route. Naturalisation can take up to 18 months from the receipt, or 12 months in some long-residence cases.	Timings are route-specific and incomplete files can slow everything down.
Is citizenship better than permanent residence?	Not always.	If you do not need a French passport, permanent residence in France may be enough.

Summary based on current French nationality guidance; route-specific requirements and individual circumstances may differ.

Route map

Birth or child route → check age and residence history
French parent or established French family line → check descent proof
Married to a French national → check declaration by marriage
Long-term resident in France → check naturalisation

Does France allow dual citizenship?

Yes. According to Service-Public.fr, it is possible to hold two or more nationalities in France. In plain English, dual citizenship or dual nationality means you are legally recognised as a national by France and by at least one other country.

France generally does not require you to give up your original nationality when you become French through naturalisation or declaration. Giambrone Law, which provides advice on French nationality matters, also points out that France permits dual citizenship. However, applicants must check whether their other country allows it as well.

• France usually lets a foreign national become French without automatic renunciation.
• A French national who acquires another nationality does not usually lose French nationality for that reason alone.
• The main confusion starts outside France, because some countries limit or forbid dual nationality.
• How to verify: check with your embassy, consulate, or your home country’s official nationality authority, not a forum or third-party list.

Who can get dual citizenship in France?

There is no standalone application called “dual citizenship France”. Instead, you qualify for French nationality through a specific route, and dual nationality is the result if your other country also allows it.

The four main routes are:

• birth or a child-related route
• descent, meaning a French parent or provable French family line
• marriage to a French national, usually by déclaration, which is a formal nationality declaration
• naturalisation, meaning a residence-based application decided by the state

By birth or as a child

Birth in France alone does not automatically make every child French. A child born in France to foreign parents may become French later, but the route depends on age and residence history, and some children are French from birth only in more specific cases.

Official guidance shows that children born in France to foreign parents may apply from age 13 or 16 if they meet residence conditions, and some become French automatically at 18 if they have lived in France for the required period. A minor can also become French when a parent becomes French and the child is included in the parent’s decree or declaration.

Checklist

• Was the child born in France?
• Has the child lived in France for the required years?
• Is the application being made in the right age window?
• If a parent became French, was the child included in that process?

By descent

French citizenship by descent usually starts with a French parent, but the practical issue is proof. Family stories, an old passport in a drawer, or a surname that “sounds French” are not enough on their own.

Where descent is unclear, the formal proof route is often the certificat de nationalité française, or CNF, which is an official certificate proving French nationality. The CNF process focuses on documents showing the legal chain of nationality and family links.

What you may need to prove

• your birth certificate and identity document
• your French parent’s birth certificate
• documents proving filiation, such as marriage or recognition records
• any decree, declaration, or earlier proof showing when the French line acquired or kept nationality
• where relevant, a longer documentary chain linking you to the first French ascendant

One thing worth knowing is that descent cases often fail on proof, not principle. If records are missing or inconsistent, verify what the tribunal or CNF process accepts before you spend money on translations.

By marriage

French citizenship by marriage is not automatic. It is a nationality déclaration, which means you must meet legal conditions and prove them, rather than simply sending in a marriage certificate.

The core rules are that the French spouse must have been French on the wedding day and must have remained French since then, the couple must show continuous shared life, and the marriage must usually be at least four years old. If you have lived abroad and spent under three years in France since the marriage, the period can rise to five years unless the French spouse was properly registered on the consular register.

1. Check that your spouse is still French.
2. Check the length of the marriage.
3. Prove continued shared life, both practical and emotional.
4. Make sure any marriage celebrated abroad has been entered in the French civil registers.
5. Be ready to prove French language ability and provide route-specific documents.

By naturalisation

For many expats, French citizenship by naturalisation is the main route. Naturalisation means the state grants nationality by decree after checking lawful residence, integration, and other conditions.

The official naturalisation rules usually start from five years of residence in France, although some people may qualify sooner under limited exceptions. In practice, that means long residence on its own is not enough if your language proof, income history, criminal record, or overall file is weak.

For naturalisation applications submitted under the rules in force from 1 January 2026, applicants generally need to demonstrate French at B2 level in both speaking and writing. They must also pass the civic examination, subject to any applicable exemptions or accommodations, and meet the residence, integration, income, and criminal-record requirements for their route.

Checklist

• lawful residence in France
• enough residence history for your route
• sufficient French language level
• evidence of integration and civic understanding
• stable and sufficient income
• no disqualifying criminal record

If you have lived in France for years but are unsure whether to apply now, the key question is whether your file is ready, not just whether enough time has passed.

What should you check before applying?

Before you pay for translations or start collecting certificates, check two things first. Does your current nationality allow dual nationality, and do you actually need citizenship now?

This is where many expats save the most time. A British national in Lyon after Brexit may find that France generally allows dual nationality, but still need to decide whether a citizenship application is worth the extra cost and scrutiny compared with residence status.

Check the rules of your current nationality

France’s rule is only half the answer. Your other country may allow dual nationality, require renunciation, impose military or civic duties, or expect you to use a certain passport when entering or leaving.

A common question is whether British nationals can keep British nationality. Usually yes, but that does not mean the answer is the same for every country, so always verify the current rules through official channels.

Checklist

• Does your country allow dual nationality?
• Would becoming French trigger renunciation rules?
• Are there passport-use rules when travelling to that country?
• Are there extra tax, civic, or military obligations to consider?

Citizenship or permanent residence: which is better?

Citizenship and residence solve different problems. Citizenship is stronger if you want a French passport, full political rights, and permanent status as a French national. Residence can be enough if your main goal is long-term stability in France.

If your home country restricts dual nationality, permanent residence in France may be the smarter next step.

Option	Who it suits	Key benefits	Key limits
Citizenship	Long-term settlers who want full nationality rights	French nationality, passport rights, stronger long-term security	More paperwork, route tests, and possible home-country conflicts
Permanent residence	People who mainly want to stay in France long term	Stable residence rights with less change to your nationality status	No French nationality, no French passport, fewer political rights

This comparison summarises general differences between French citizenship and permanent residence; eligibility and individual rights may vary.

What are the requirements and documents?

The detail changes by route, but the broad pattern is consistent. France wants to know who you are, how you qualify, whether your records are reliable, and whether your route-specific conditions are met.

Document area	Typical examples	Why it matters
Identity	Passport or residence permit	Confirms who is applying
Civil status	Birth, marriage, divorce records	Proves family links and route
Residence	Address proof, residence history	Shows eligibility and continuity
Language	Certificate where required	Supports integration checks
Nationality evidence	Parent’s French record, decree, declaration, CNF	Proves the legal nationality route

Document examples are indicative only; the exact list depends on your nationality route and personal circumstances.

Language, residence and integration requirements

Across routes, readers will keep seeing the same themes: residence history, French language level, integration, financial stability, and criminal record checks. The exact mix depends on the route, so avoid assuming one rule fits every file.

For naturalisation, Service-Public says applicants must show sufficient French, civic understanding, stable and sufficient income, and no serious disqualifying convictions. If you are preparing for an interview, review the livret du citoyen, or citizen’s booklet, and be ready to explain your life in France in a clear, consistent way.

Checklist

• verify the language requirement for your route
• collect evidence of lawful and continuous residence where needed
• prepare tax and income records
• check whether an interview is likely
• read the route-specific official guidance before booking tests

Documents, translations and legalisation

Most nationality files need identity documents, birth or marriage records, proof of address, and route-specific nationality evidence. Some applicants also need foreign criminal record extracts, especially where the official route says they are required.

Small errors cause big delays. A spelling mismatch, a document issued too long ago, or a record missing a parent’s details can mean your file is paused, returned, or challenged.

Checklist

• passport or official ID
• full birth certificate, and marriage certificate if relevant
• proof of address in France
• proof of nationality route, such as a parent’s French record or a CNF
• criminal record extract where the route requires it
• certified French translations, plus apostille or legalisation if needed

How do you apply for dual citizenship in France?

The process depends on the route, but the order is usually similar.

1. Confirm the right route.
2. Gather the route-specific documents.
3. Submit to the correct authority.
4. Attend an interview if your route requires one.
5. Monitor the decision and react quickly to any request for more evidence.

Simple timeline

Route check	Document gathering	Submission	Interview or follow-up	Decision and possible appeal

This timeline provides a general overview; submission methods, interviews, and processing stages vary by route and place of residence.

Where to apply

There is no single desk for every case. Naturalisation often goes through a plateforme de naturalisation, which is the state nationality platform for your area, while some child and CNF matters go through the tribunal, and people abroad may need a French consulate.

The correct office can also change depending on whether you live in France or overseas. How to verify: check the local official platform before sending anything, because the wrong office can cost you months.

• plateforme de naturalisation for many naturalisation and marriage files
• préfecture, the local state office, for route guidance or local handling in some cases
• tribunal judiciaire for some child or CNF matters
• consulate if you live abroad

Interview, timelines and appeals

The interview usually checks whether your file matches your real situation and, for some routes, how well you are integrated into French society. That is why a complete file matters so much. If the paperwork is weak, the interview often becomes harder, not easier.

For naturalisation, the administration generally has up to 18 months from the issue of the receipt to respond. This is reduced to 12 months if you have lived habitually in France for at least 10 years, although the administration may extend the deadline once by up to three months if it explains why.

1. Expect timings to vary by route and local workload.
2. Assume incomplete files will slow things down.
3. Keep every receipt and submission proof.
4. If refused, check the decision notice for the correct appeal path and deadline.

What rights and limits come with dual citizenship in France?

Dual nationality can make life in France simpler, but it does not cancel every rule in your other country. The benefit is broader status, not a clean legal reset.

What you gain as a dual citizen

As a French national, you can live and work in France as a citizen, not as a foreign resident. You can also move forward with getting a French passport once your nationality is established.

That matters in real expat life because it can mean fewer worries about long-term status, easier family planning, and more flexibility about where you live in future.

• access to a French passport
• full nationality rights in France
• stronger long-term settlement security
• political rights where the law allows
• wider freedom linked to French citizenship

What can still be limited or complicated?

Dual nationality can still come with extra obligations. Your other country may keep tax, military, civic, or passport-use rules, and France’s recognition of dual nationality does not cancel them.

One thing worth knowing is that French diplomatic protection has limits for dual nationals. If you are in the territory of your other nationality, France may not be able to treat you as French for consular protection purposes. The reverse logic also applies in France.

• home-country tax or reporting obligations may continue
• military or civic obligations may still apply in the other country
• passport rules can differ when entering your other country
• French consular protection may be limited while you are in the other country of nationality
• nationality can still be affected by fraud, misrepresentation, or route-specific loss rules

What does dual citizenship cost and how can you manage the admin?

The official application cost is only part of the bill. You also need to budget for record copies, translations, apostilles or legalisation, travel to appointments, and the time cost of correcting paperwork.

Last checked: official French nationality fees, forms, and timeline guidance on Service-Public and Expatica on 16 June 2026. Nationality rules change, and outcomes depend on the route, residence history, language proof, criminal record, and the law of your other country, so this guide is informational only and not legal advice.

Official fees, translations and supporting costs

For naturalisation and nationality by marriage, the current official timbre fiscal, or tax stamp, is €255 according to current Service-Public guidance. Some proof routes, such as a CNF request, are free, but the surrounding admin can still add up.

Budgeting checklist

• official nationality fee, where your route has one
• certified translations into French
• apostille or legalisation if needed
• replacement birth or marriage records
• travel to the tribunal, consulate, or interview
• optional professional help if your case is complex

Managing cross-border money during the process

Some applicants need to move money between countries while they gather documents, pay translators, travel for appointments, or manage life across two homes. That is an admin issue, not an eligibility issue.

If you need to pay international costs during the process, one practical option is Wise for international transfers or holding multiple currencies. It does not affect whether you qualify for French nationality, and it is not part of the official procedure.

Sources

• Service-Public.fr — Peut-on avoir plusieurs nationalités en France ?: https://www.service-public.gouv.fr/particuliers/vosdroits/F334
• Service-Public.fr — Nationalité française: https://www.service-public.gouv.fr/particuliers/vosdroits/N111
• Service-Public.fr — Naturalisation française par décret: https://www.service-public.gouv.fr/particuliers/vosdroits/F2213
• Service-Public.fr — Déclaration de nationalité française par mariage: https://www.service-public.gouv.fr/particuliers/vosdroits/F2726
• Service-Public.fr — Nationalité française d’un enfant né en France de parents étrangers: https://www.service-public.gouv.fr/particuliers/vosdroits/F295
• Service-Public.fr — Certificat de nationalité française (CNF): https://www.service-public.gouv.fr/particuliers/vosdroits/F1051
• Service-Public.fr — Perte volontaire de la nationalité française: https://www.service-public.gouv.fr/particuliers/vosdroits/F3073
• Service-Public.fr — Annulation, retrait ou déchéance de nationalité française: https://www.service-public.gouv.fr/particuliers/vosdroits/F32827
• Giambrone Law — Applying for dual citizenship in France: https://www.giambronelaw.com/site/advice/gaining-citizenship/french-citizenship/paths-to-french-citizenship/dual-citizenship-in-france/