You share a French address, a joint current account and years of life together, yet under French law you are still two strangers. After Brexit, British citizens are third-country nationals. A long-stay visitor card, a Withdrawal Agreement card or even a French house does not, by itself, give your partner the status of a spouse. If one of you dies without a will, the survivor is not an heir. If the tax office looks at a gift or a legacy between you, the default rate between unrelated persons is 60 per cent. If the préfecture (the local State administration that issues residence cards) is asked for a family residence card, a PACS certificate is only one exhibit among others.

The French answer to that gap is the pacte civil de solidarité (civil solidarity pact, almost always called a PACS). Article 515-1 of the Civil Code defines it in a single sentence: “Un pacte civil de solidarité est un contrat conclu par deux personnes physiques majeures, de sexe différent ou de même sexe, pour organiser leur vie commune.” It is a contract between two adults, of different or same sex, to organise their life together. Service-Public, the official government portal, confirmed on 10 April 2026 that a PACS is open whatever your nationality. It is not a marriage, it does not change your name, it does not make you a legal heir, and it does not, on its own, force the préfecture to issue a carte de séjour vie privée et familiale (temporary residence card marked “private and family life”).

This guide is written for a British unmarried couple living in France, or about to settle, who need to know how to register a PACS after Brexit, which UK papers the mairie (town hall) or the notaire (notary) will actually accept, what the contract changes for income tax and inheritance, and how to challenge a refusal by the town hall, the notary or the préfecture. It sits beside, and does not replace, the separate questions of a tontine or joint ownership clause on the home, an English will over a French house, or a residence card as the spouse of a French citizen.

I. How do we sign a French PACS after Brexit, and what if the town hall refuses our file?

A. Which documents do British partners need, and does a UK civil partnership replace a French PACS?

The PACS is registered, not celebrated. Article 515-3 of the Civil Code states: “Les personnes qui concluent un pacte civil de solidarité en font la déclaration conjointe devant l’officier de l’état civil de la commune dans laquelle elles fixent leur résidence commune ou, en cas d’empêchement grave à la fixation de celle-ci, devant l’officier de l’état civil de la commune où se trouve la résidence de l’une des parties.” You make a joint declaration before the registrar of the commune where you fix your common residence, or, if a serious impediment prevents that, before the registrar of the commune where one of you lives. The same article adds that the partners must produce their convention (the written contract) “à peine d’irrecevabilité” (on pain of inadmissibility). The registrar stamps it and gives it back. You may instead go to a notary: “Lorsque la convention de pacte civil de solidarité est passée par acte notarié, le notaire instrumentaire recueille la déclaration conjointe, procède à l’enregistrement du pacte et fait procéder aux formalités de publicité prévues à l’alinéa précédent.” Registration at the mairie is free; a notarial deed is paid. In Paris, the file is lodged at the mairie of the arrondissement of the common residence; in the rest of Île-de-France, at the mairie of the commune. A notary in Paris or Nanterre, Versailles or Créteil will register the same contract if you prefer a deed and advice on the property clause.

The contract has no effect between you until it is registered. Article 515-3-1 of the Civil Code is explicit: “Le pacte civil de solidarité ne prend effet entre les parties qu’à compter de son enregistrement, qui lui confère date certaine. Il n’est opposable aux tiers qu’à compter du jour où les formalités de publicité sont accomplies.” A signed convention left in a drawer is not a PACS. Publicity is a mention in the margin of each partner’s birth record, or, for a foreign national born abroad, on a register kept by the central civil-status service of the Ministry for Europe and Foreign Affairs.

The impediments are short and they are nullities. Article 515-2 of the Civil Code provides: “A peine de nullité, il ne peut y avoir de pacte civil de solidarité : 1° Entre ascendant et descendant en ligne directe, entre alliés en ligne directe et entre collatéraux jusqu’au troisième degré inclus ; 2° Entre deux personnes dont l’une au moins est engagée dans les liens du mariage ; 3° Entre deux personnes dont l’une au moins est déjà liée par un pacte civil de solidarité.” You cannot PACS with a parent, child or sibling, nor if either of you is already married, nor if either of you is already bound by a PACS. A UK civil partnership is not a French marriage. French law treats “liens du mariage” as marriage. The Cour de cassation (France’s highest ordinary court) has refused to treat a PACS as marriage even where the social picture looks similar. In Civ. 1re, 28 February 2018, no. 17-10.876, published, the Court held: “l’alliance étant établie par le seul effet du mariage, la qualité de partenaire d’un pacte civil de solidarité n’emporte pas incapacité à être témoin lors de l’établissement d’un testament authentique instituant l’autre partenaire légataire”. Alliance, in the technical sense, is produced only by marriage. A PACS partner is not an in-law. That is why a UK civil partnership, which is not a French marriage, does not by itself produce the French tax household, the French inheritance-tax exemption or the French one-year housing right attached to a PACS. If you already have a UK civil partnership and now live in France, the safe course is to ask the mairie or the notary in writing whether they will register a French PACS, and to keep the answer. Do not assume that the British status “replaces” the French contract.

Service-Public, page F1618, verified on 10 April 2026, lists the papers. Each partner produces a full copy or an extract of the birth certificate showing parentage, not more than six months old at the date of registration, unless the foreign civil-status system does not update birth records. The United Kingdom does not annotate a birth certificate with later marriage or partnership. In that case the same page requires an attestation from the embassy, consulate or another competent authority of the country of origin stating that the record is not updated. If the document is not in French, it must be translated by a traducteur assermenté (sworn translator). Depending on the country, an apostille or a legalisation may also be required. The United Kingdom is a party to the Hague Apostille Convention, so a UK birth certificate used in France is typically apostilled rather than legalised. The detail of that apostille, which French préfectures also demand on residence files, is explained in our note on the UK birth certificate apostille after Brexit.

A British partner born abroad must also produce a certificat de non-Pacs (certificate of non-PACS) less than three months old. Service-Public, page F35102, verified on 29 October 2025, states that a foreign national born abroad who wishes to enter a PACS must supply a certificat de non-Pacs. The certificate issued also covers non-registration in the civil directory and the annexed civil directory. The request is made online or by post to the Service central d’état civil. A British partner born in France follows a different path and produces a French birth extract instead.

French practice still asks many foreigners for a certificat de coutume (certificate of custom) describing the personal-status law of the country of origin, and for proof that the person is of age, unmarried and legally capable. The UK does not issue a French-style certificate of celibacy. The Foreign, Commonwealth and Development Office publishes a self-declaration form for British nationals who marry or register a PACS in France, for use in place of certificates of celibacy and custom. That form, with the accompanying notes on British birth certificates and change of name, is the document to bring to the mairie or the notary, together with the apostilled birth certificate and the certificat de non-Pacs. Some Paris arrondissements still ask for extra papers. Ask for a written list. Do not rely on a conversation at the counter.

You also lodge Cerfa no. 15725 (joint declaration and solemn statements of non-kinship, non-alliance and common residence) and either a tailor-made convention or Cerfa no. 15726 (the standard-form convention). The default property regime, unless you write otherwise, is set by article 515-5 of the Civil Code: “Sauf dispositions contraires de la convention visée au troisième alinéa de l’article 515-3 , chacun des partenaires conserve l’administration, la jouissance et la libre disposition de ses biens personnels.” Each partner keeps administration, enjoyment and free disposal of personal assets. Assets that neither can prove as exclusive property “sont réputés leur appartenir indivisément, à chacun pour moitié” (are deemed to belong to them jointly, half each). If you own a French house together, that default is not a tontine (a clause under which the survivor is deemed never to have shared ownership). The PACS does not, by itself, send the house to the survivor. If that is the aim, the ownership clause and the will have to be drawn separately.

The obligations start on registration. Article 515-4 of the Civil Code provides: “Les partenaires liés par un pacte civil de solidarité s’engagent à une vie commune, ainsi qu’à une aide matérielle et une assistance réciproques. Si les partenaires n’en disposent autrement, l’aide matérielle est proportionnelle à leurs facultés respectives.” Life together, material help and mutual assistance. Unless you agree otherwise, the material help is in proportion to each partner’s means. The same article makes the partners jointly liable to third parties for debts contracted by either of them for ordinary household needs, with exceptions for manifestly excessive spending, hire-purchase and most loans. The Cour de cassation applies that duty when the PACS later breaks down. In Civ. 1re, 27 January 2021, no. 19-26.140, published, the Court quoted article 515-4 and held that mortgage payments made by the better-off partner “participaient de l’exécution de l’aide matérielle entre partenaires” (formed part of the performance of material help between partners), so that partner had no personal claim to be reimbursed for those payments after the PACS was dissolved. A British couple who put the French house and the loan in unequal shares should take that case into the convention, in writing, before they sign.

B. What if the mairie or notary refuses to register the PACS?

The registrar is not free to invent extra conditions, but the registrar is bound to refuse an incomplete or prohibited file. Article 515-2 is a nullity. If one of you is still married in England and Wales, even after years of separation, there is no French PACS until the decree absolute exists. If a previous French PACS has not been dissolved, there is no second PACS. Dissolution itself is mechanical. Article 515-7 of the Civil Code states: “Le pacte civil de solidarité se dissout par la mort de l’un des partenaires ou par le mariage des partenaires ou de l’un d’eux.” It also dissolves by joint declaration or by a unilateral notice served on the other partner. Between the partners, dissolution takes effect on registration; against third parties, on completion of the publicity formalities. A British partner who has married someone else in the UK should expect the French PACS to end by operation of law, and should not leave the French publicity uncorrected.

The usual British refusals at the counter are documentary. The birth certificate is too old, or it is a short certificate without parentage, or it has no apostille. The certificat de non-Pacs is more than three months old. The self-declaration is unsigned, or the sworn translation is missing. The convention has not been produced. The common residence is not in the commune. Article 515-3 requires the joint declaration before the registrar of the commune of the common residence. A second-home owner who still lives in Kent cannot treat a Dordogne mairie as the place of common residence merely because the house is there. The 90/180-day visitor who has no French residence at all is not in the situation contemplated by article 515-3. A PACS is not a way around the Schengen clock.

When the mairie or the notary refuses, ask for the refusal in writing, with the legal ground. A verbal “come back with more papers” is not a decision you can appeal, but it is a list you can satisfy. If the registrar claims a legal impediment that is not in article 515-2, or refuses a UK self-declaration that the Foreign Office issues specifically for a French PACS, the next step is a written complaint to the mayor as head of the civil-status service, then, if needed, an application to the tribunal judiciaire (ordinary court) of the place of the mairie. In Paris that is the Tribunal judiciaire de Paris; in the inner suburbs it is often Nanterre, Bobigny, Créteil or Versailles, depending on the département. Deadlines and forms differ from a préfecture appeal. Do not send the town-hall file to the administrative court by mistake.

A notary who refuses to receive the deed should also put the reason in writing. A notary is entitled to refuse a convention that the notary considers unlawful or a client who will not produce the identity and capacity papers. A notary is not entitled to refuse because the partners are British. If the obstacle is only the UK paperwork, the same apostille, non-Pacs certificate and FCDO self-declaration that the mairie requires will usually unlock the deed. Keep copies of every email. The date of registration is the date the PACS takes effect between you. A delay of three months is not a small thing if one partner is ill or if a gift is planned.

Once registered, the PACS can be modified by a new convention sent to the same registrar or notary, under article 515-3. It can be dissolved under article 515-7 without a judge, unlike a divorce. That ease of exit is the counterpart of the limited protection. It is also why a PACS, standing alone, is a poor substitute for a will, a tontine, or, where the couple wants the full status of spouses, a marriage. The registrar’s job is to record the contract you actually signed, not to rebuild your estate plan.

II. What does a PACS change for tax, inheritance and residence, and how do we challenge a préfecture or tax refusal?

A. Joint tax, the 60 per cent inheritance trap, and why a PACS is not a will

On income tax, the PACS is close to marriage. Article 6 of the General Tax Code provides: “Les partenaires liés par un pacte civil de solidarité défini à l’article 515-1 du code civil font l’objet, pour les revenus visés au premier alinéa, d’une imposition commune. L’imposition est établie à leurs deux noms.” Partners bound by a PACS as defined in article 515-1 are jointly assessed on the income referred to in the first paragraph. The assessment is in both names. Service-Public, page F1026, verified on 27 January 2026, repeats the practical consequence: you file one joint income-tax return. One tax notice is issued in both names. You are jointly liable for the tax. In the year the PACS is registered, article 6, paragraph 5, of the same code adds: “Les personnes mariées et les partenaires liés par un pacte civil de solidarité sont soumis à une imposition commune pour les revenus dont ils ont disposé pendant l’année du mariage ou de la conclusion du pacte.” They may, however, opt for separate assessment of the income each personally had in that year, plus that partner’s share of common income. The option is irrevocable and must be exercised within the time limit for the original income return. It is not available if partners who already had a PACS in an earlier year later marry each other. In the year of dissolution or death, paragraph 6 splits the year. A British couple who PACSs in June should diary the option, because UK pensions, UK rental income and French salaries in the same calendar year can make a joint return more expensive than two separate ones, or the reverse.

Inheritance is the point on which many British couples are mis-sold a PACS as if it were a marriage. It is not. Article 734 of the Civil Code lists the orders of heirs “En l’absence de conjoint successible”: children and their descendants; parents, brothers and sisters; other ascendants; other collaterals. The PACS partner is not in that list. Service-Public, page F1621, verified on 16 June 2026, states the result without ornament: without a will, PACS partners cannot inherit from one another, and for inheritance they are treated as strangers to one another. The one legal courtesy on the home is temporary. Article 515-6 of the Civil Code provides: “Lorsque le pacte civil de solidarité prend fin par le décès d’un des partenaires, le survivant peut se prévaloir des dispositions des deux premiers alinéas de l’article 763 .” Article 763 gives the surviving spouse, for one year, rent-free enjoyment of the main home and its furniture where that home belonged to the couple or fell entirely into the estate. Article 515-6 extends the first two paragraphs of that article to the surviving PACS partner. It is a year, not ownership. After the year, the heirs — often the deceased’s children from a first marriage, or brothers and sisters in England — can demand partition. A will, and where the house is jointly owned a carefully drawn clause, remain indispensable. Our separate guides on the English will and a French house and on tontine and joint ownership between unmarried partners deal with those instruments. The PACS does not replace them.

Tax on the inheritance, if there is a will, is a different question from the right to inherit. Between persons who are not relatives, article 777 of the General Tax Code, Table III, sets the rate “Entre parents au-delà du 4e degré et entre personnes non-parentes” at 60. That is the rate that hits a British cohabitant who is left the French house by will and who never PACSed. With a PACS, the tax picture changes. Article 796-0 bis of the General Tax Code provides: “Sont exonérés de droits de mutation par décès le conjoint survivant et le partenaire lié au défunt par un pacte civil de solidarité.” The surviving spouse and the surviving PACS partner are exempt from inheritance transfer duties. The official tax commentaries BOI-ENR-DMTG-10-50-30 of 29 September 2014 and BOI-ENR-DMTG-10-20-10 of 30 June 2022, and Service-Public page F17456 verified on 13 May 2026, describe the same exemption for the PACS partner. Service-Public also warns that the deceased must still have made a will if the partner is to take any part of the estate, and that a succession declaration must still be filed. The exemption is not a reason to skip the return.

Two traps remain. First, the exemption follows a PACS that exists at death. A couple who “meant to PACS next spring” is still in the 60 per cent column of article 777. Second, a PACS with someone else can destroy a different exemption. In Com., 28 May 2025, no. 21-16.632, published, the Cour de cassation linked article 515-4 to article 796-0 ter of the General Tax Code, the sibling exemption. It held: “Selon le premier de ces textes, les partenaires liés par un pacte civil de solidarité s’engagent à une vie commune.” Then: “Il en résulte que l’exonération prévue par ce dernier texte ne peut bénéficier à une personne qui, au jour de l’ouverture de la succession, était liée à un tiers par un pacte civil de solidarité.” A person bound by a PACS to a third party is no longer “célibataire” (single) for that sibling relief. The PACS is a real bond, not a label you can pick up and put down for tax convenience.

If the tax office ignores the PACS and issues a 60 per cent assessment, the challenge is a réclamation (formal tax claim) against the assessment, then, if needed, the administrative court. Keep the PACS registration, the will, the succession declaration and the tax notice together. The legal ground is the exemption described by the BOFIP commentaries and Service-Public, not a plea to fairness. If the office accepts that you were PACSed but denies that a particular asset formed part of the exempt share, the fight moves to valuation and to whether the will actually disposed of that asset. None of that is solved by producing only a joint council-tax bill or a UK civil-partnership certificate.

B. Residence card after PACS: why the préfecture can still refuse, and how to appeal

Marriage to a French citizen has its own residence article. Article L. 423-1 of the Code on the Entry and Residence of Foreigners and the Right of Asylum (CESEDA) provides that the foreign spouse of a French national “se voit délivrer une carte de séjour temporaire portant la mention ” vie privée et familiale ” d’une durée d’un an” when cohabitation has not ceased, the spouse has kept French nationality, and a marriage celebrated abroad has been transcribed. There is no equivalent automatic sentence for a PACS. The PACS partner of a French citizen, or of a British resident, is assessed under the general private-and-family-life article. Article L. 423-23 of CESEDA states: “L’étranger qui n’entre pas dans les catégories prévues aux articles L. 423-1, L. 423-7, L. 423-14, L. 423-15, L. 423-21 et L. 423-22 ou dans celles qui ouvrent droit au regroupement familial, et qui dispose de liens personnels et familiaux en France tels que le refus d’autoriser son séjour porterait à son droit au respect de sa vie privée et familiale une atteinte disproportionnée au regard des motifs du refus, se voit délivrer une carte de séjour temporaire portant la mention ” vie privée et familiale ” d’une durée d’un an, sans que soit opposable la condition prévue à l’article L. 412-1.” The ties are assessed in particular by reference to their intensity, duration and stability, the foreigner’s living conditions, insertion into French society and the nature of ties with family left in the country of origin.

Service-Public, page F2209, lists the “convention de PACS” among the proofs of matrimonial and family ties, next to a marriage extract. It also asks for proof by any means of certain and continuous relations with family in France, including a partenaire pacsé. The PACS is on the list. It is not the whole list. Village-Justice has made the same point for practitioners: the pact is one element of the foreigner’s private life among others. Justifit’s 2025 PACS guide walks through household debts, default separation of property, income tax and the need for a will, but it is written for a French reader and does not describe a préfecture investigation after Brexit. For a British partner, the missing pieces are the lawful-stay path, the proof of actual cohabitation, and the appeal.

The administrative courts treat a recent PACS as a starting point, not as a key to the door. The Cour administrative d’appel of Nantes, in 12 April 2024, no. 23NT03059, examined a foreign national of whom the court wrote: “M. C… se prévaut de sa communauté de vie avec une ressortissante française, Mme B…, avec laquelle il a conclu un pacte civil de solidarité le 23 juin 2021.” He produced a social-housing contract in both names, bills, photographs and statements. The court accepted that those papers were “un commencement de preuve que les deux pacsés vivent effectivement ensemble”, as the court put it. The préfecture had still commissioned a cohabitation inquiry. The police report of 25 February 2022 concluded that a community of life and a regular presence with the partner could not be attested. The court held that the circumstances relied on “ne suffisent pas, compte tenu en particulier de la brièveté de sa vie commune avec Mme B…, à établir qu’en refusant de lui délivrer un titre de séjour, le préfet aurait méconnu les dispositions de l’article L. 423-23 du code de l’entrée et du séjour des étrangers et du droit d’asile, les stipulations de l’article 8 de la convention européenne de sauvegarde des droits de l’homme et des libertés fondamentales ou aurait entaché sa décision d’une erreur manifeste d’appréciation”. A PACS of a few months, thin evidence of daily life, and weak insertion will not carry article L. 423-23. A British partner who PACSs on Monday and files on Tuesday, with no French, no work, no lease in both names and no history of cohabitation, should expect a refusal or a long silence.

The file that does survive a préfecture interview looks prosaic: the PACS registration, the convention, a lease or title in both names, joint bank statements, bills at the same address over a useful period, the partner’s French identity card or residence card, and, where the applicant is still on a visitor card, proof that the visitor conditions were respected until the change of status. A visitor card is not a work permit; a PACS does not, by itself, convert it. Our note on renewing a visitor card after Brexit remains relevant until the family card is granted. In Paris the application is made to the Préfecture de police, usually through ANEF (the national foreigner-application portal). In the rest of Île-de-France it is the préfecture of the département — Hauts-de-Seine, Seine-Saint-Denis, Val-de-Marne, Yvelines, Essonne, Val-d’Oise or Seine-et-Marne. Book the appointment as soon as the PACS is registered. Keep screenshots of ANEF receipts. An implied refusal after a statutory silence can be appealed, but only if you can prove the date of the complete application.

A written refusal is an administrative decision. Article L. 211-1 of the Code of Administrative Justice provides: “Les tribunaux administratifs sont, en premier ressort et sous réserve des compétences attribuées aux autres juridictions administratives, juges de droit commun du contentieux administratif.” The administrative courts are the ordinary judges of that dispute. Article R. 421-1 of the same code adds: “La juridiction ne peut être saisie que par voie de recours formé contre une décision, et ce, dans les deux mois à partir de la notification ou de la publication de la décision attaquée.” The court may be seised only by a challenge against a decision, and within two months of notification or publication. In Paris the court is the Tribunal administratif de Paris; for much of the inner suburbs it is the Tribunal administratif of Melun, Cergy-Pontoise or Versailles, depending on the préfecture that signed. A prior administrative appeal to the prefect does not always stop the two-month clock. Read the letter. If the letter mentions an obligation to leave French territory, other, shorter, specialised time limits may apply and the case is no longer a simple residence-card dispute. Do not wait for a “second review” that the letter does not grant.

The grounds that work on appeal are those in article L. 423-23 itself: intensity, duration and stability of the life together, insertion, and proportionality of the refusal. A PACS certificate without a shared home will not be enough, as Nantes shows. A long, documented cohabitation that the préfecture ignored, or a police inquiry that never visited the address, can be enough. Order-public refusals rest on a different article, L. 432-1 of CESEDA, which allows a motivated refusal where the foreigner’s presence is a threat to public order. That is not a paperwork issue. It needs the underlying conviction or conduct, and a separate defence.

Two British profiles should not be confused. A Withdrawal Agreement beneficiary who already holds a French residence document is not asking to be let in; the PACS then matters for family members who are still outside that scheme. A newcomer on a visitor visa who PACSs with a French citizen is asking for a first family card under L. 423-23 and will be judged on actual family life. Marriage remains the more direct statutory path under L. 423-1 if the couple is willing and able to marry. A PACS is faster to register and easier to dissolve. It is also easier for the préfecture to treat as inconclusive. Choose the instrument for the right it actually confers, not for the name it has in a British conversation.

Conclusion

A French PACS after Brexit is worth doing, and worth doing properly. It is the contract that organises the life together, creates a joint tax household under article 6 of the General Tax Code, opens the inheritance-tax exemption described by the tax authorities for a partner who actually inherits, and gives the survivor one year in the home under articles 515-6 and 763 of the Civil Code. It does not make you an heir, it does not transfer the house, it does not copy a UK civil partnership, and it does not bind the préfecture to issue a family residence card. Register it at the mairie of the common residence or before a notary, with an apostilled UK birth certificate, a certificat de non-Pacs, the FCDO self-declaration and a convention you have actually read. Make a will the same week. If the town hall refuses the file, demand the legal ground in writing and go to the tribunal judiciaire. If the tax office assesses 60 per cent as if you were strangers, claim the PACS exemption with the registration and the will. If the préfecture refuses the residence card, appeal to the administrative court within two months with proof of a real common life, not only the Cerfa. That is the difference between a PACS that works and a PACS that exists only on paper.

Need a quick opinion on your case.

Talk the PACS file, the will and the residence or tax letter through with an avocat before the mairie appointment, before the préfecture decision, or before the two-month appeal deadline expires. Our firm offers a telephone consultation within 48 hours with an avocat of the firm. Call +33 6 46 60 58 22 (Maître Reda Kohen), or reach us through our contact page. We assist British residents and owners in Paris and across the Paris region as well as throughout France.