You live together, you are not married, you are not in a civil partnership, and you own a house in France. For thousands of British couples this is the reality after Brexit: a cottage in Normandy, a flat in Paris, a farmhouse in the Dordogne, bought together years ago, lived in full time or used for long stays. While both partners are alive everything feels simple. One of you pays the insurance, the other deals with the plumber, and the French tax office sends the same bills either way. The difficulty starts on the day one partner dies. French law does not treat an unmarried partner as family. The survivor has no automatic right to stay, no protected share, and faces the heaviest rate of French death tax. The deceased partner’s half can pass to children, parents, siblings or even distant relatives, and those heirs can, in principle, demand that the whole house be sold.

This guide is written entirely for a British reader and explains every French term the first time it appears. Indivision is joint ownership, where each person owns an undivided share of the whole. A quote-part is that share, for example one half each. The tontine, also called a clause d’accroissement, is a special clause that can be written into the purchase deed under which the survivor is treated as having owned the whole property from the start. The notaire is the French public officer who draws up authentic deeds for property. Droits de mutation à titre gratuit are the French transfer duties on gifts and successions. The partage is the partition that ends joint ownership. The licitation is the sale by auction or private sale of jointly owned property to end the dispute, or the buyout of the other shares by one co-owner. With those definitions in place, this pillar article covers the whole cluster: what ordinary joint ownership means while both partners live, what a tontine adds and where it stops working, what tax the survivor pays as a legal stranger, which law governs the succession of a Briton in France since Brexit, and the practical routes for staying in the home or buying out the heirs, including how to check and challenge a wrong assessment.

I. If you buy a French home together without marrying, who owns what while you both live?

The default position for two British buyers who are not married and not in a French pacte civil de solidarité, the registered civil partnership known as PACS, is joint ownership in undivided shares. You each own half of everything, not half of the house each in the English sense of separate halves. The kitchen, the garden, the roof: all of it belongs to both of you together. That structure is flexible while you agree, and fragile as soon as you disagree, because French law gives every co-owner a permanent right to leave.

A. We bought our French house 50/50 in joint ownership: can my partner force a sale?

Yes. The starting rule of French joint ownership is blunt, and it applies to British unmarried partners exactly as it applies to French co-owners. Article 815 of the French Civil Code provides: “Nul ne peut être contraint à demeurer dans l’indivision et le partage peut toujours être provoqué, à moins qu’il n’y ait été sursis par jugement ou convention.” In plain English, nobody can be forced to stay in joint ownership, and partition can always be demanded, unless a court or a contract has ordered a temporary stay. The official text is published in the French Civil Code, Article 815.

For a British couple this has three immediate consequences. First, either partner can demand partition at any time during their joint lives, even if the other wants to keep the house for holidays or retirement. Second, after one partner dies, that same right passes to the deceased partner’s heirs, who step into the shoes of the deceased for their share. Third, no private letter, English cohabitation agreement or informal promise that you will never sell overrides the statute unless it takes the form of a valid French joint-ownership agreement that meets strict formalities.

French law does allow co-owners to organise their joint ownership by contract. Article 1873-1 of the Civil Code states: “Ceux qui ont des droits à exercer sur des biens indivis, à titre de propriétaires, de nus-propriétaires ou d’usufruitiers peuvent passer des conventions relatives à l’exercice de ces droits.” In plain English, people who hold rights over jointly owned property, as owners, bare owners or usufruct holders, may enter into agreements about how those rights are exercised. The official text is in the French Civil Code, Article 1873-1. The next article adds the formality: “Les coïndivisaires, s’ils y consentent tous, peuvent convenir de demeurer dans l’indivision.” In plain English, all the co-owners acting together may agree to remain in joint ownership. The official text is in the French Civil Code, Article 1873-2.

In practice a French convention d’indivision, a joint-ownership agreement, must be in writing, must identify the property and each person’s share, and must comply with registration formalities where the property is land. It can appoint a manager, fix who pays what, regulate occupation, and, within limits, postpone partition for a fixed period. It cannot suppress the right to partition forever. A British couple who bought 50/50 should therefore ask their notaire three questions before any dispute: is there a written joint-ownership agreement, what does it say about duration and management, and has it been properly registered so it binds successors. Without such an agreement, the default rule is full freedom to demand partition.

Day-to-day management also needs unanimity for serious acts. Selling, mortgaging or granting a long lease over the whole house normally requires both partners. Where one partner refuses unreasonably and the common interest is at risk, French law provides a safety valve. Article 815-5 of the Civil Code provides: “Un indivisaire peut être autorisé par justice à passer seul un acte pour lequel le consentement d’un coïndivisaire serait nécessaire, si le refus de celui-ci met en péril l’intérêt commun.” In plain English, a co-owner can be authorised by a court to carry out alone an act that would normally need the other’s consent, where the other’s refusal endangers the common interest. The official text is in the French Civil Code, Article 815-5. Urgent measures can be ordered even faster. Article 815-6 provides: “Le président du tribunal judiciaire peut prescrire ou autoriser toutes les mesures urgentes que requiert l’intérêt commun.” In plain English, the president of the judicial court may order or authorise all urgent measures required by the common interest. The official texts are in the French Civil Code, Article 815-5 and the French Civil Code, Article 815-6. These are emergency tools, not a way to run the house alone permanently. They cover a leaking roof, an unpaid insurance premium, or a buyer who will walk away if one signature is missing. They do not give one partner the right to sell the other’s share for convenience.

British readers should also understand what marriage would have changed, precisely so they do not assume they benefit from it. French law gives a surviving spouse who actually lived in the home as their main residence a free one-year right to stay. Article 763 of the Civil Code provides: “Si, à l’époque du décès, le conjoint successible occupe effectivement, à titre d’habitation principale, un logement appartenant aux époux ou dépendant totalement de la succession, il a de plein droit, pendant une année, la jouissance gratuite de ce logement, ainsi que du mobilier, compris dans la succession, qui le garnit.” In plain English, if at the time of death the surviving spouse actually occupies as their main home a dwelling belonging to the spouses or depending entirely on the succession, they have as of right, for one year, free use of that dwelling and of the furniture it contains. The official text is in the French Civil Code, Article 763. The same article adds that these rights are deemed direct effects of marriage, not succession rights, and that the provision is a matter of public policy. An unmarried partner, a concubin or concubine in French, has no equivalent statutory right to stay. That single difference explains why so many British cohabiting couples ask about the tontine: without marriage, without PACS, and without a tontine, the survivor is legally a stranger to the deceased’s half.

B. What does a tontine clause change for British unmarried buyers in France?

The tontine is the clause many British estate agents in France mention, often too quickly. Properly drafted and inserted in the purchase deed at the time of acquisition, it can protect the survivor far better than ordinary joint ownership. Poorly understood, it creates a false sense of security and a heavy tax bill that arrives exactly when the survivor is most vulnerable.

The legal mechanism is unusual and must be quoted exactly. In an opinion of 15 June 2022, the Court of Cassation stated: “La clause de tontine, ou clause d’accroissement, est celle par laquelle, lorsque plusieurs personnes acquièrent un bien, le survivant des acquéreurs est réputé avoir été seul propriétaire depuis l’acquisition.” In plain English, the tontine clause, or accretion clause, is the clause by which, where several persons acquire property together, the survivor is deemed to have been the sole owner since the acquisition. The full decision is published as Avis of the Court of Cassation of 15 June 2022, Nos 21-80.743 and 22-70.002, available on the Court of Cassation, Avis 15 June 2022.

That retroactive fiction is the whole point. If James and Sarah, both British, buy a house in Brittany 50/50 with a tontine clause, and James dies first, Sarah is deemed to have owned the whole house from day one. James’s heirs do not inherit half a house. In principle they have nothing to partition and nothing to sell. The survivor keeps the roof without having to buy out anyone. For unmarried partners who have no children together and who want the home to go to the survivor rather than to distant relatives, this is the protection ordinary joint ownership cannot provide.

Four limits must be understood before relying on it. First, the clause must be in the acquisition deed itself, not added later by private letter. A tontine added after purchase, or promised orally by the agent, has no effect on third parties or the tax administration. British buyers should check the French deed, the acte authentique de vente, for the exact words clause de tontine or clause d’accroissement. If those words are absent, there is no tontine, whatever was said at the viewing.

Second, the tontine is treated as a gamble with tax consequences. For succession purposes the survivor is deemed to receive the deceased’s share by death, and where the partners are not married or in a PACS, that transmission is taxed as between strangers. The rate and the small allowance are examined in Part II below. The key point here is that civil protection and tax protection are different things. The tontine can solve the civil problem of keeping the house, while leaving the tax problem intact. A survivor who keeps a 400,000 euro house but must pay six-figure duties within months has not been fully protected.

Third, the tontine can be recharacterised in family situations where it looks like a disguised gift that harms protected heirs. In a judgment of 12 January 2022 (First Civil Chamber, No 20-12.232, published in the Bulletin), the Court of Cassation upheld a Court of Appeal which had treated a tontine agreement contained in a flat purchase deed as a disguised gift from the deceased to his wife, subject to the special equalisation rules for gifts to a surviving spouse. The decision is available on the Court of Cassation, 12 January 2022, No 20-12.232. That case concerned a married couple and the fairness rules between heirs, combining Articles 758-5 and 758-6. Article 758-5 provides: “Le calcul du droit en toute propriété du conjoint prévu aux articles 757 et 757-1 sera opéré sur une masse faite de tous les biens existant au décès de son époux auxquels seront réunis fictivement ceux dont il aurait disposé, soit par acte entre vifs, soit par acte testamentaire, au profit de successibles, sans dispense de rapport.” The official text is in the French Civil Code, Article 758-5. Article 758-6, cited in the judgment, governs how gifts received by the surviving spouse are set against succession rights. The official text is in the French Civil Code, Article 758-6. For unmarried British partners the lesson is narrower but real: where the tontine was funded very unequally, for example where one partner paid the whole price but the deed shows 50/50 with tontine, heirs can argue that the clause hides a gift and ask the court to bring it back into account. Equal contributions, clean bank records and honest shares in the deed reduce that risk.

Fourth, do not try to replicate a tontine through a property company that holds only the house. Some British buyers are told to put the house in a French société civile immobilière, a non-trading property company known as a SCI, and to write a tontine over all the shares. The Court of Cassation has struck down that exact arrangement. In a judgment of 9 April 2026 (Third Civil Chamber, No 25-12.992), the Court of Cassation held that a company-article clause providing for accretion or tontine over the shares contradicts the rule that a company must be formed by two or more persons, and annulled the company on that ground. The decision is available on the Court of Cassation, 9 April 2026, No 25-12.992. The underlying company rule is Article 1832 itself, which provides: “La société est instituée par deux ou plusieurs personnes qui conviennent par un contrat d’affecter à une entreprise commune des biens ou leur industrie en vue de partager le bénéfice ou de profiter de l’économie qui pourra en résulter.” The official text is in the French Civil Code, Article 1832. A clause that leaves only one shareholder standing contradicts the very definition of a company. British partners who already own through a SCI should have the articles reviewed, and should not add a whole-share tontine as a cheap fix.

Where does that leave a British unmarried couple buying today. Ordinary joint ownership is simple and cheap, but leaves the survivor exposed to partition and to 60 percent tax on the deceased’s half. A tontine in the purchase deed can secure the house civilly for the survivor, but it does not remove the tax, it must be drafted at the right time, and it works best where contributions were broadly equal. Marriage or PACS changes the tax completely, because gifts and successions between spouses and PACS partners fall under a different tariff table, while transmissions between unmarried partners fall under the strangers’ rate examined below. That choice is personal and has consequences far beyond the house, for residence, social protection and wider succession. Take separate advice before marrying for a house alone. For couples who remain unmarried, the honest question is not whether the tontine is magic, but whether keeping the house is worth the tax that will fall due on first death, and whether life cover, a will choosing the applicable law, and a clear buyout plan would serve the survivor better.

II. When one British partner dies, how does the survivor keep the home and challenge the tax bill?

Death transforms the file. While both partners live, the questions are management and harmony. After one death, three different bodies of rules apply at once: French succession law decides who inherits the deceased’s share, French tax law decides what the survivor or the heirs pay, and European private international law decides which country’s succession rules apply to a Briton who owned land in France after Brexit. The survivor who understands all three can act quickly. The survivor who confuses them can lose the home, overpay tax, or miss a deadline.

A. My partner died owning half our French home: will I pay 60 percent tax as a non-relative?

In most cases, yes, unless you were married or in a PACS, or unless a valid tontine reshapes who is deemed to receive what. French law treats an unmarried cohabitant as a stranger for death tax. The deceased partner’s half share in ordinary joint ownership forms part of the deceased’s succession. It does not pass automatically to the survivor. It passes to the deceased’s heirs under the applicable succession law: children first, then parents and siblings, then wider family, then a will beneficiary if the will is valid. The survivor keeps their own half and has no right over the other half except by will, by tontine, or by buying it from the heirs.

The tax scale is set by Article 777 of the General Tax Code. The article fixes duties by tables according to the net share received by each beneficiary, with Table I for the direct line, Table II for transfers between spouses and PACS partners, and Table III for the collateral line and transfers between non-relatives. For the last category the text provides: “Entre parents au-delà du 4e degré et entre personnes non-parentes 60”. In plain English, the rate is 60 percent for relatives beyond the fourth degree and for non-relatives. The official text is in the General Tax Code, Article 777. British unmarried partners fall squarely in that last line. Spouses and PACS partners are taxed under the far lighter Table II described in the same article as “Tarif des droits applicables entre époux et entre partenaires liés par un pacte civil de solidarité”. Unmarried cohabitants are not in that table.

A worked example makes the trap concrete. Take a house in the Dordogne worth 360,000 euros, owned 50/50 without tontine. On the death of one partner, the deceased’s half is worth 180,000 euros. The survivor, as a non-relative, is taxed at 60 percent on what they receive from that half, subject only to a very small allowance, while the heirs who take instead of the survivor are taxed according to their own family link. If the survivor receives the half by will, the bill on 180,000 euros at 60 percent is over 100,000 euros, payable within short deadlines, before any British tax is considered. If a valid tontine applies, the analysis shifts civilly because the survivor is deemed to have owned the whole from the start, but the tax administration still taxes the value accruing to the survivor on first death as a transfer between strangers at the same heavy rate. Either way the survivor must plan for cash, not just bricks.

The territorial reach of French death tax is deliberately wide, and Brexit did not narrow it. Article 750 ter of the General Tax Code provides: “Sont soumis aux droits de mutation à titre gratuit : 1° Les biens meubles et immeubles situés en France ou hors de France, et notamment les fonds publics, parts d’intérêts, biens ou droits composant un trust défini à l’article 792-0 bis et produits qui y sont capitalisés, créances et généralement toutes les valeurs mobilières françaises ou étrangères de quelque nature qu’elles soient, lorsque le donateur ou le défunt a son domicile fiscal en France au sens de l’article 4 B ;” In plain English, movable and immovable property in France or abroad is subject to French transfer duties where the donor or the deceased had their tax domicile in France. The same article then taxes French-sited property even where the deceased was not domiciled in France, and taxes property received by an heir domiciled in France under conditions of prior residence. The official text is in the General Tax Code, Article 750 ter. For British owners this means three common cases are all caught: a British resident of France who dies owning a French house, a British resident of England who dies owning a French holiday home, and in some cases a British heir living in France who inherits foreign assets. Domicile, the location of the house, and the heir’s residence must all be checked. Do not assume that living in Kent takes the Dordogne house outside French tax.

Which succession law decides who gets what is a separate question from tax, and it is governed since 2015 by the European Succession Regulation No 650/2012. The United Kingdom never opted into that Regulation, but France applies it to everyone who dies habitually resident in France or owning land there. The default rule is that the whole succession is governed by the law of the deceased’s last habitual residence, unless the deceased chose in a will the law of their nationality. A British citizen habitually resident in France who says nothing is therefore governed in principle by French law, including French forced-heirship rules for children. A British citizen who writes into a valid will that English law, or Scots law for a Scot, shall govern the succession can in principle opt for that national law. The official text of the Regulation is on EU Succession Regulation No 650/2012. The French administration explains the same choice-of-law logic for international successions on Service-public.fr, International successions, and the French tax administration sets out how to declare a succession and pay duties on Impots.gouv.fr, Succession and gifts. On the British side, the rules on wills, probate and Inheritance Tax are on GOV.UK, Wills, probate and inheritance.

For unmarried British partners this choice of law matters enormously. French law gives children a protected share that limits gifts and wills, while English law gives a testator much wider freedom. Choosing English law in a will does not remove French tax, and it does not create a forced share for the surviving unmarried partner, because English law itself gives no automatic share to a cohabitant. What it can do is avoid the application of French forced heirship to the deceased’s half where the deceased leaves children from an earlier relationship and wants to favour the surviving partner by will within English limits. Conversely, doing nothing and letting French law apply can protect the deceased’s children but leave the surviving partner with nothing from the deceased’s half. There is no single right answer. A British will covering French land must be valid in form, must contain an express choice of law if that is wanted, must be coordinated with any tontine, and must be shown to the French notaire in a certified translation with an apostille where required. An English grant of probate alone does not transfer French land. The French notaire settles the French succession on the basis of French conflict rules, the will, and the land register.

Practical steps in the first weeks after death are therefore strict. First, secure the will, the purchase deed, any joint-ownership agreement, and proof of who paid what. Second, instruct the French notaire quickly, because French declarations have short time limits and interest runs on late duties. Third, ask the notaire to confirm in writing whether a tontine exists, what share the deceased owned, which law governs the succession, who the heirs are, and what allowance and rate apply to each beneficiary. Fourth, do not empty the house, sell furniture, or move money from joint accounts before advice, because those acts can have succession and tax consequences. Fifth, keep the British and French files together: death certificate, marriage or PACS certificate if any, will, probate, valuations, and every tax assessment. The file that pays the right amount is the file where the civil analysis came first and the tax computation followed it.

B. My partner died and the family wants to sell: how can the surviving partner stay or buy them out?

Where there is no tontine, or where the tontine fails on its facts, the survivor co-owns the house with the deceased’s heirs. Each side can invoke Article 815 and demand partition. In practice that means three outcomes: agreement to stay together temporarily, buyout of one side by the other, or sale of the whole house and division of the price. Courts prefer agreement, then buyout, then sale. Forcing a sale of a family home occupied by the survivor is possible but is the last resort, and the survivor has tools to delay, to stay, or to take the house at a fair price.

The first tool is a temporary joint-ownership agreement with the heirs. Relying again on Articles 1873-1 and 1873-2, the survivor and the heirs can sign a written convention d’indivision that names a manager, fixes contributions to insurance, tax and repairs, regulates occupation and compensation, and postpones partition for an agreed period. That breathing space lets the survivor arrange finance, lets minor heirs grow up, or lets the market improve. The agreement must be unanimous, written, and registered where land is concerned. A short agreement of one or two years, renewable, is often more credible to heirs than a demand for ten years. Offer transparency on costs and access in return for time.

The second tool is attribution or buyout. French partition law allows a co-owner who wants to keep the property to ask for it to be allocated to them in the partition, against payment of compensation, the soulte, to the others. The Court of Cassation confirmed that a co-owner can ask to be allocated the whole property on partition of conventional joint ownership, subject to the statutory conditions and against payment of compensation to the others. That solution was laid down in a published judgment of the First Civil Chamber of 3 December 2014, No 13-27.627, available on the Court of Cassation, 3 December 2014, No 13-27.627. For a surviving partner this is the cleanest route to keep the home: obtain an independent valuation, the valeur vénale, offer to take the house at that value, and pay the heirs their shares in cash. Where the survivor already owned half, only the other half is bought, and the registration duty on a buyout that ends joint ownership is the reduced 2.5 percent duty on partitions, not the full sale duty, under Article 750 of the General Tax Code, which taxes qualifying partitions that end joint ownership at 2.5 percent. The official text is in the General Tax Code, Article 750. That reduced duty does not remove the succession duties examined above, which are due in any event on what the survivor receives from the deceased. It only lightens the later buyout step.

The third route, where agreement fails, is court-ordered partition and, if the house cannot be divided in kind, licitation, the sale of the whole with division of the price. Either side can petition the judicial court. The court will first try to allocate, then order sale if allocation is impossible or uneconomic. A farmhouse with one kitchen cannot be cut in two. The survivor can bid at the sale like anyone else, but bidding at auction without finance in place is dangerous. Better to arrive with a valuation, a mortgage principle, and a written offer to the heirs before the hearing. Judges notice who behaved reasonably.

Valuation disputes are where British survivors most often overpay or lose. French tax and partition both turn on the open-market value at the relevant date, not on the price paid years ago, not on the insured value, and not on an estate agent’s optimistic email. Commission a written valuation from a qualified local agent or surveyor who has seen the house, supports the figure with comparable sales, and states the effect of any tenancy, disrepair, planning risk or co-ownership charges. Keep photographs, diagnostics, and quotes for essential works. If the tax office values the half share higher than your valuer, you can challenge the assessment through the notaire and then through the formal complaint channels shown on the notice, within the time limits printed on it. Act fast, pay what is indisputably due where possible so interest stops on that part, and argue the balance with evidence. The French tax administration explains declarations and remedies on Impots.gouv.fr, Succession and gifts, and the public service site explains the steps after a death on Service-public.fr, What to do after a death.

Life on the ground also needs immediate protection. Change nothing on the land register without advice. Keep buildings insured and heated. Continue paying the taxe foncière, the French property tax, and the co-ownership charges to avoid penalties that will later be set against you. Keep every receipt, because occupation compensation, the indemnité d’occupation, and reimbursement of expenses are calculated from paperwork, not memory. If heirs demand that you leave, do not leave under pressure without a court order or a signed agreement fixing the date, the condition of the property, and who pays what until then. If you need to stay urgently, ask the court for interim measures under Article 815-6, which, as quoted above, allows the president of the judicial court to order urgent measures required by the common interest, including provision for urgent needs or appointment of an administrator. Use that sparingly and with evidence.

A final warning on paperwork from England. British families often arrive with an English will, a lasting power of attorney, or a letter of wishes, and expect the French notaire to apply them directly. Since Brexit those documents need more preparation, not less. The will must be proved, translated, and where required apostilled. The choice of English law must be express to have effect under the European Regulation applied by France. Powers of attorney made for English purposes do not manage French land after death. The grant of probate does not transfer French land by itself. Bring originals, bring translations, and let the French notaire say what is effective in France. The files that end with the survivor staying are the files where the tontine was checked on day one, the governing law was identified, the valuation was evidenced, the heirs received a funded buyout offer, and every deadline was met. The files that end in forced sale are the files where the survivor assumed that paying half the price years ago meant owning the whole house forever.

Conclusion

For British unmarried partners with a French home, the civil answer and the tax answer point in opposite directions. Civilly, ordinary joint ownership leaves each half free to pass to heirs who can demand sale, while a well-drafted tontine in the purchase deed can keep the whole house in the survivor’s hands by deeming the survivor sole owner from the start. Fiscally, the survivor remains a stranger: 60 percent on what is received from the deceased, with only a small allowance, whether the route is inheritance, will or tontine accretion. Add the wide reach of French death tax over French houses even where the deceased lived in Britain, the choice between French and British succession law under the European Regulation, and the strict formalities for joint-ownership agreements, valuations and buyouts, and the need for early, coordinated advice in both countries becomes clear. Check the deed for the tontine wording, confirm the governing law, obtain an evidenced valuation, make a funded offer for the other half where there is no tontine, and challenge any wrong assessment promptly with documents. The survivor who does that work keeps options open. The survivor who waits for family consensus while deadlines run down keeps none.

Need a quick opinion on your case.

If you own a French home with your partner without being married, get advice before a death or a dispute forces a sale. Our firm offers a telephone consultation within 48 hours with a lawyer of the firm to review your deed, your tontine clause, your will and your tax position. Call +33 6 46 60 58 22 or write to us through our contact page with a copy of your purchase deed and any will.