Your baby has just been born in a French maternity ward. You are both British, you live in France on a Withdrawal Agreement card or a long-stay visa, and the midwife asks a question you cannot answer with confidence: what nationality is your child? The French birth certificate will say the baby was born in France, but that alone does not make the child French. British nationality law may make the child British, but only if at least one parent holds the right kind of British citizenship. And the French nationality your child might want later, for university fees, public-sector jobs or simply belonging, depends on school certificates you should start keeping today. This guide explains the position step by step: the nationality your child holds on day one and how to prove it, the travel document a British minor needs in France, the declaration windows at thirteen and sixteen that let the family claim French nationality early, and the automatic route at eighteen with the residence test the courts apply strictly. Every French term is explained as it appears, and every decisive rule is tied to the official text behind it.

I. On the day of birth, your French-born baby is British, not French, and the paperwork starts now

A. Why being born in France does not make a British baby French, and how British citizenship passes to the child

France does not apply an unconditional right of the soil. Article 18 of the Civil Code states the filiation rule in one sentence: “Est français l’enfant dont l’un des parents au moins est français.” In plain terms, a child is French at birth only if at least one parent is French. Where both parents are British, that route is closed on day one, however long the family has lived in France and whether the birth took place in Paris, Lyon, Bordeaux or a village maternity unit.

Parents sometimes hope for the safety net of Article 19-1 of the Civil Code, which provides: “Est français : 1° L’enfant né en France de parents apatrides ; 2° L’enfant né en France de parents étrangers pour lequel les lois étrangères de nationalité ne permettent en aucune façon qu’il se voie transmettre la nationalité de l’un ou l’autre de ses parents.” This covers children who would otherwise be stateless, born in France to stateless parents or to parents whose national laws cannot transmit nationality at all. It does not help a British family, because British law does transmit nationality to children born abroad in the standard case. The child of British parents is therefore not stateless, and Article 19-1 does not apply.

British nationality on day one comes from section 2(1) of the British Nationality Act 1981, under which a child born outside the United Kingdom is a British citizen where at least one parent at the time of the birth is a British citizen otherwise than by descent, subject to the further conditions set out in that section. The key distinction is between a British citizen otherwise than by descent, typically someone born in the United Kingdom or naturalised there, and a British citizen by descent, typically someone who was themselves born abroad and inherited British citizenship from a parent. If at least one parent is British otherwise than by descent, the baby born in France is automatically a British citizen by descent. If both parents are themselves British only by descent, the baby is not automatically British at birth, and the family must look at registration routes, notably the entitlement provisions for children born abroad in sections 3(2) and 3(5) of the 1981 Act, explained in the Home Office caseworker material published on registration of children as British citizens. Families in that second situation should take advice early rather than assume the child holds British citizenship.

Parents should understand precisely what the phrase otherwise than by descent covers, because it decides whether the child is British automatically or needs registration. A parent born in the United Kingdom, or naturalised as a British citizen after settlement there, is normally British otherwise than by descent, and transmits citizenship to a child born in France. A parent who is British only because his or her own parent was British, having been born abroad without ever being naturalised in the United Kingdom, is British by descent and does not transmit citizenship automatically to the next generation born outside the country. Where the automatic route fails, the family turns to registration: the Home Office guidance distinguishes discretionary registration of any minor from the entitlement routes for children whose parents later live in the United Kingdom for a qualifying period. Registration is an application with a fee and supporting evidence, not a passport application, and it should be started while the qualifying residence facts are fresh. A further optional step is consular registration of the birth, which creates a United Kingdom record of the event but does not itself confer nationality; useful as evidence, it never replaces the passport or the registration certificate as proof of citizenship.

Two practical consequences follow. First, get the French civil-status paperwork right immediately: the maternity unit declares the birth to the town hall, the mairie, of the place of birth, and the mairie draws up the acte de naissance, the birth certificate. Order several full copies, copies intégrales d’acte de naissance, because consulates, the Home Office and later the French nationality desk all ask for them. Second, apply for the child’s British passport through the standard overseas route and keep the French birth certificate with the British passport together: for the next eighteen years, that pair of documents is the simplest proof of who the child is, where the child was born and which nationality the child holds.

A question many parents ask at this stage is whether the child can hold both nationalities later. Both France and the United Kingdom accept dual nationality, so a child who becomes French at thirteen, sixteen or eighteen does not have to give up British citizenship to do so, and becoming French does not erase the British citizenship by descent acquired at birth. The two nationalities simply coexist, each with its own passport and its own consular protection.

B. Living in France as a British minor: the travel document, the residence position and the file you must keep

Since Brexit, a British child born in France is a third-country national minor. Daily life, school enrolment and healthcare access generally follow the parents’ position, but travel does not: the child needs a personal travel setup to leave France and be readmitted. That setup is the DCEM, the document de circulation pour étranger mineur, the circulation document for a foreign minor. The official service-public.fr page on the DCEM explains that this document must be requested for a foreign minor who travels outside France, that it is presented alongside the passport for readmission at the French or external Schengen border, and that it is issued for a maximum of five years. The application is made by at least one parent holding a valid residence permit, and where the child is under thirteen the document is valid for five years, aligned where necessary with the expiry of the parent’s own permit. Families who visit grandparents in the United Kingdom every school holiday should treat the DCEM expiry date with the same seriousness as a passport expiry date, because an expired DCEM discovered at the airport means a postponed journey.

At eighteen the position changes. The child, still British at that point unless French nationality has been acquired earlier, needs a residence permit in his or her own right. The route most often relevant is the vie privée et familiale, private and family life, permit for a young person who grew up in France, described on service-public.fr. Parents who themselves hold Withdrawal Agreement cards should check the exact permit the child qualifies for well before the eighteenth birthday, since a child born in France after the end of free movement does not automatically hold a Withdrawal Agreement status. Where the wider family project involves relatives still in the United Kingdom, the rules for relatives joining a British resident in France are explained in our guide on bringing a spouse and children to France, with visa steps and refusal remedies.

Schooling and healthcare follow the child’s real life rather than nationality. A child resident in France must be enrolled in school from the age of three, and the mairie of residence and the school cannot refuse enrolment because the child is British; proof of address and the birth certificate suffice. Healthcare cover attaches through the parents, whether through employed or self-employed affiliation, private insurance in the early months, or universal cover once residence is stable, and the child is registered as a dependant, an ayant droit, on the parent’s health record. Separated parents should keep the custody order or parenting agreement with the nationality file, because declarations at thirteen and travel authorisations later may require proof of who exercises parental authority, autorité parentale, and a missing signature is the commonest avoidable cause of a rejected filing.

The single most valuable habit from birth onwards is keeping proof of continuous life in France. French nationality at thirteen, sixteen and eighteen turns entirely on documented habitual residence, résidence habituelle, proved year by year. Keep every certificat de scolarité, school attendance certificate, medical and vaccination records, taxe d’habitation and utility paperwork showing the family address, and any official correspondence naming the child at that address. The reason is the burden of proof rule in Article 30 of the Civil Code: “La charge de la preuve, en matière de nationalité française, incombe à celui dont la nationalité est en cause.” Only the holder of a certificat de nationalité française, the nationality certificate, reverses that burden. Until the family holds that certificate, every gap in the paper trail is a risk, and a year of unprovable residence can be the year that defeats a declaration, as the case law below shows.

II. How your child becomes French: the early declaration windows and the automatic route at eighteen

A. Claiming French nationality at thirteen or sixteen: who applies, what to prove and where to file

French law does not make British parents wait until the child is eighteen. Article 21-11 of the Civil Code opens two early windows: “L’enfant mineur né en France de parents étrangers peut à partir de l’âge de seize ans réclamer la nationalité française par déclaration, dans les conditions prévues aux articles 26 et suivants si, au moment de sa déclaration, il a en France sa résidence et s’il a eu sa résidence habituelle en France pendant une période continue ou discontinue d’au moins cinq ans, depuis l’âge de onze ans. Dans les mêmes conditions, la nationalité française peut être réclamée, au nom de l’enfant mineur né en France de parents étrangers, à partir de l’âge de treize ans, la condition de résidence habituelle en France devant alors être remplie à partir de l’âge de huit ans.” The official explanation of these routes, with the lists of supporting documents for each age band, is published on service-public.fr and should be read alongside the statute.

In practice the thirteen-year route is a parental application: the parents claim French nationality on behalf of the child, with the child’s consent required, and must show habitual residence in France since the age of eight. The sixteen-year route is the child’s own declaration, requiring habitual residence since the age of eleven. Both routes require residence in France on the day of the declaration, and the five years may be continuous or broken, continue ou discontinue, which helps families whose child spent a few months abroad, provided the total and the pattern still satisfy the test. The consent requirement matters: a teenager who does not want French nationality cannot have it imposed through these declarations, subject only to the narrow case of a minor unable to express wishes for certified medical reasons.

Declarations are filed under Articles 26 and following of the Civil Code. Article 26 provides: “Les autres déclarations de nationalité sont reçues par le directeur des services de greffe judiciaires du tribunal judiciaire ou par le consul.” It adds that the formalities are set by decree in the Conseil d’Etat and that “Il en est délivré récépissé après remise des pièces nécessaires à la preuve de leur recevabilité.” In ordinary language, the nationality declaration for a child in France is received by the registrar, the greffier, of the local tribunal judiciaire, the civil court, which issues a receipt once the file contains the documents needed to show it is admissible. Prepare the file as a litigator would: full birth certificate, parents’ passports and residence permits, proof of the child’s residence year by year, school certificates covering the whole reference period, and evidence of the parents’ own continuous residence. If the registrar refuses to register the declaration, that refusal can be contested before the tribunal judiciaire, and the public prosecutor, the ministère public, may also challenge a registration it considers unfounded. A refusal letter should therefore be kept with the receipt and the complete copy of the filed bundle, because the court will examine exactly what was filed and when.

If the registrar refuses to register the declaration, the family is not at the end of the road. The refusal must be reasoned, and the remedy is an application to the tribunal judiciaire, which re-examines the residence evidence in full and can order registration where the conditions are met. The hearing turns on documents rather than speeches: school certificates for each year of the reference period, housing and tax evidence tying the child to the French address, and an explanation with proof for every absence, such as a term spent abroad or a hospital stay. Because the public prosecutor is a party to nationality litigation and may itself contest a registration, the file should be built once, completely, and kept identically for every later step, so that the declaration bundle, the nationality certificate request and any court action all tell the same documented story.

Timing strategy matters. A family confident about the paper trail often prefers the thirteen-year declaration, which secures French nationality before the secondary-school years when identity documents, travel for school trips and part-time work all become easier with French nationality. A family with a thinner file, for example after an expatriation posting abroad during the child’s primary years, may deliberately wait for sixteen or eighteen to accumulate the five qualifying years. What the family should never do is nothing: each birthday narrows the options, and the evidential position only hardens while school records are still easy to obtain. Ask the school for duplicate attendance certificates before changing schools or academies, because a closed school file is far harder to reconstruct five years later.

B. French automatically at eighteen: the five-year residence test the courts enforce strictly

If no declaration was made earlier, Article 21-7 of the Civil Code can make the child French automatically at majority: “Tout enfant né en France de parents étrangers acquiert la nationalité française à sa majorité si, à cette date, il a en France sa résidence et s’il a eu sa résidence habituelle en France pendant une période continue ou discontinue d’au moins cinq ans, depuis l’âge de onze ans.” Three conditions must coincide on the eighteenth birthday: birth in France to foreign parents, residence in France at majority, and habitual residence for at least five years since the age of eleven. No application is needed in theory, but proof is needed in practice, because any authority, employer, university or prefecture that doubts the position will ask for the nationality certificate, and the Cour de cassation reads the residence condition narrowly.

The leading practical lesson comes from the Court of Cassation, First Civil Chamber, 5 September 2018, appeal number 17-23.255. A man born in France to Spanish parents claimed French nationality acquired at majority and argued from his legal domicile. The Court approved the appeal judges’ reasoning that the claimant, in its words, “qui invoquait un domicile légal sans apporter la preuve d’une résidence habituelle en France dans les cinq années précédant sa majorité, soit depuis l’âge de 13 ans, n’avait pas acquis la nationalité française à sa majorité”. Legal domicile is not habitual residence: what counts is where the young person actually and habitually lived, proved with documents, during the five years before majority. For a British family this is a direct warning about boarding school in England, a gap year with grandparents in the United Kingdom or a posting abroad that interrupts the child’s French schooling. Each of those episodes must be measured against the five-year reference period, and a file showing four provable years instead of five fails the test.

The same decision contains a second useful point on possession d’état, the consistent treatment of a person as French by the authorities. The appeal court had dismissed an invalidity card mentioning French nationality as too old and uninformative to count. The Court of Cassation quashed on that head under Article 21-13 of the Civil Code, holding that the judges had to consider the card, as an official document issued by the prefecture mentioning French nationality. The message for families is symmetrical: official documents that treat the child as French have evidential weight, so keep identity cards, certificates and administrative correspondence, but they do not replace the core proof of five years’ habitual residence.

The burden point is confirmed by an earlier decision, First Civil Chamber, 10 July 2013, appeal number 12-21.357. A woman born in France to foreign parents argued that her father’s posting abroad for a French bank should count as assimilated residence benefiting the whole family. The Court rejected the argument, holding that assimilation of residence abroad for service to France benefits only the person exercising the activity, or that person’s spouse living with them, and the daughter had therefore not acquired French nationality automatically at majority: “l’assimilation à la résidence en France, au sens de l’article 78 du code de la nationalité, ne bénéficiant qu’à l’étranger exerçant cette activité ou à son époux s’ils habitent ensemble”. Combined with Article 30’s rule that the person whose nationality is at issue carries the burden of proof, the practical conclusion is stark: the family proves the five years, document by document, and nobody else does it for them. Parents seconded abroad by a British employer, or splitting time between London and France, should map every school term against the reference period before relying on the automatic route.

When the file is solid, the family should convert the position into an unchallengeable document by requesting a certificat de nationalité française from the registrar of the tribunal judiciaire. Once that certificate is issued, Article 30 reverses the burden: anyone disputing the child’s French nationality must prove the challenge. If the certificate is refused, or if a prefecture or administration disputes the automatic acquisition, the remedy is the declaratory action on nationality, the action déclaratoire de nationalité, before the tribunal judiciaire, where school records, medical records, housing evidence and witness material are examined together. Families planning the whole residence project, from arrival visas to the child’s adult status, will find the broader entry framework in our guide for British newcomers choosing the right long-stay visa and residence permit, with refusal and OQTF remedies.

The nationality certificate deserves emphasis because it ends arguments. The request is filed with the registrar of the tribunal judiciaire of the child’s home, with the birth certificate, the parents’ documents and the full residence file, and the registrar investigates before issuing or refusing the certificate. Once issued, the certificate is the standard proof demanded by prefectures for residence permits, by universities for fee status and by employers for posts reserved to nationals, and under Article 30 any challenger must disprove it. If the registrar refuses the certificate while the family believes the conditions of Article 21-7 or 21-11 are met, the same court action carries the dispute: the tribunal judiciaire declares whether the child is French, and its judgment, once final, is recorded on the birth certificate in the margin, the mention en marge, so that every later copy of the acte de naissance shows the French nationality. That marginal note is the finishing line of the whole process started in the maternity ward.

Conclusion

A baby born in France to British parents starts life as a British citizen by descent where at least one parent is British otherwise than by descent, and as a non-French minor who needs a DCEM to travel and a personal residence permit at eighteen. French nationality then follows the child’s real life in France: a parental declaration from thirteen with residence proved since eight, the child’s own declaration from sixteen with residence proved since eleven, or automatic acquisition at eighteen with five years’ habitual residence since eleven. The courts test those five years on facts, not on domicile labels, and the family carries the burden of proof until the nationality certificate is in hand. Keep the birth certificate, the passports, the DCEM renewals and above all the school certificates for every single year, and each of the three doors to French nationality stays open when the family chooses to walk through it.