You live in the United Kingdom, you own a holiday home in the Dordogne, the Luberon or the Charente, and you have decided to sell. Since 1 January 2021 you have been selling as a third-country national: the United Kingdom is no longer in the European Union, and French tax law treats your sale differently from the sale made by your neighbour who lives in Lyon or even by an Irish owner. France taxes the gain first, at the signing table, before the money reaches you. The United Kingdom taxes the same gain second, through your Self Assessment return, with relief for the French tax. Between those two certainties sits a set of very practical questions that decide how much you keep: how the 19 per cent French levy is calculated, how years of ownership shrink the taxable base, when only the 7.5 per cent solidarity charge is due instead of the full schedule of French social charges, whether you must appoint an accredited tax representative in France, and what to do when the bill looks wrong or nobody warned you it was coming.

This guide answers those questions in order. It explains the French levy on non-resident sellers, the exact statutory texts behind it, and the treaty machinery that prevents the same euro of gain from being taxed twice in full. It walks through signing day: the capital-gains return the notaire (the French public-officer conveyancer who alone can transfer the property) files, the withholding taken from the price, and the accredited representative you must appoint when the price exceeds the legal threshold. It then shows, with two recent French court decisions, why the tax simulation must arrive before you sign the preliminary contract, and how to challenge an excessive assessment or a professional who failed to warn you. Every decisive proposition below is tied to the official text or decision it comes from, so you can check it yourself.

I. How does France tax a UK resident who sells a French second home after Brexit?

A. What is the 19% levy, how is your taxable gain calculated, and what reliefs cut the bill?

France taxes you because the property is in France, not because you live there. Article 244 bis A of the French General Tax Code (Code général des impôts) provides: “Sous réserve des conventions internationales, les plus-values, telles que définies aux e bis et e ter du I de l’article 164 B , réalisées par les personnes et organismes mentionnés au 2 du I lors de la cession des biens ou droits mentionnés au 3 sont soumises à un prélèvement selon les taux fixés au III bis.” In plain terms, gains on the sale of buildings or rights over them, made by a person who is not fiscally domiciled in France, are subject to a withholding-style levy (prélèvement) at the rates set further down the same article, subject always to what the tax treaty says. The treaty point matters because the France-United Kingdom double tax convention decides which country may tax and which country must relieve double taxation, as explained in section I.B below. The categories of taxable gains are those defined at e bis and e ter of Article 164 B of the General Tax Code, and the full scope of the levy is set by Article 244 bis A of the General Tax Code, read together with Article 150 U of the General Tax Code, which frames taxable property gains.

For an individual seller the rate is straightforward. Article 244 bis A continues: “les personnes physiques, les associés personnes physiques de sociétés, groupements ou organismes dont les bénéfices sont imposés au nom des associés et les porteurs de parts, personnes physiques, de fonds de placement immobilier mentionnés à l’article 239 nonies sont soumis au prélèvement au taux de 19 %.” A British individual selling a French second home therefore pays income tax at 19 per cent on the taxable gain. The same 19 per cent appears for residents in Article 200 B of the General Tax Code: “Les plus-values réalisées dans les conditions prévues aux articles 150 U à 150 UC sont imposées au taux forfaitaire de 19 %.” Companies that own the house through a French or foreign vehicle are taxed differently, at the corporation-tax rate of Article 219, and the rest of this guide assumes you own the property directly, as most British second-home owners do. If you hold the house through a société civile immobilière (SCI, the French family property company), the analysis changes, and our companion guide on the SCI for British families explains that structure.

The starting point of the calculation is deliberately simple. Article 150 V of the General Tax Code states: “La plus ou moins-value brute réalisée lors de la cession de biens ou droits mentionnés aux articles 150 U à 150 UC est égale à la différence entre le prix de cession et le prix d’acquisition par le cédant.” Gross gain equals sale price minus purchase price. Statutory adjustments to each side of that subtraction exist, so the figure in the draft computation must be checked line by line rather than accepted on sight. What shrinks the bill most, for long-held holiday homes, is time itself: the duration-of-ownership relief (abattement pour durée de détention). The official tax commentary sets it out exactly. For income tax, the official commentary allows six per cent of the gain to escape for each year of ownership from the sixth to the twenty-first, with a further four per cent for the twenty-second year. In other words, from the sixth year of ownership each additional year wipes out six per cent of the gain, the twenty-second year wipes out the final four per cent, and after twenty-two full years no income tax remains. See the official duration-relief commentary. For social charges the timetable is longer: 1.65 per cent a year over the same early stretch, 1.60 per cent for the twenty-second year, then nine per cent for each year beyond. Full exemption from social charges therefore needs thirty years. A Dordogne farmhouse bought in 2010 and sold in 2026, held sixteen full years, already escapes 66 per cent of income tax on the gain and a proportionate slice of social charges — which is why the first question at any pre-sale meeting should be the exact acquisition date, proved by the old deed.

Take a worked example to see the mechanics. Suppose you bought for 200,000 euros in 2010 and sell for 330,000 euros in 2026, with sixteen full years of ownership and no other adjustments. The gross gain is 130,000 euros. Income-tax relief of 6 per cent for each of the eleven years from year six to year sixteen removes 66 per cent, leaving a taxable base of 44,200 euros, taxed at 19 per cent, which is 8,398 euros. Social-charge relief of 1.65 per cent for each of the same eleven years removes 18.15 per cent, leaving a base of about 106,405 euros, charged at the rates examined in section I.B. Because the net taxable gain sits below 50,000 euros, the surtax described in the next paragraph does not arise on these figures. Every number in that example follows directly from the texts quoted above; a real file adds the statutory price adjustments and any applicable exemptions, which is exactly what the pre-signing simulation must show.

Large gains attract an extra layer. Article 1609 nonies G of the General Tax Code creates “une taxe sur les plus-values réalisées dans les conditions prévues aux articles 150 U et 150 UB à 150 UD par les personnes physiques” and, Relevantly for you, “dans celles prévues à l’article 244 bis A par les contribuables non domiciliés fiscalement en France assujettis à l’impôt sur le revenu.” Non-resident sellers are therefore inside the surtax. The trigger is clear: “La taxe est due à raison des plus-values imposables d’un montant supérieur à 50 000 €, selon le barème suivant appliqué au montant total de la plus-value imposable”. The scale runs from 2 per cent to 6 per cent of the total taxable gain, and “Elle est due par le cédant et exigible lors de la cession” — due from the seller, payable at the sale. The official commentary gives the full progressive table, starting at two per cent for gains just above the threshold and rising to six per cent beyond 260,000 euros, with smoothing bands at each step. Two points deserve attention. First, the 50,000-euro threshold counts the net taxable gain, after duration relief, so extra years of ownership can pull a sale back under the line. Second, where several people sell together, each seller is assessed separately: the commentary confirms that unmarried partners and co-owners in undivided ownership (indivision) each count as a single seller for the threshold. A couple selling jointly therefore faces the surtax only if each share exceeds the line, not merely because the total does.

One exemption deserves a mention even though it rarely helps a second-home owner. If the house you are selling was your main home in France on the day you moved your tax residence out of France, Article 244 bis A exempts the gain on a double condition: “la cession soit réalisée au plus tard le 31 décembre de l’année suivant celle du transfert par le cédant de son domicile fiscal hors de France et que l’immeuble n’ait pas été mis à la disposition de tiers, à titre gratuit ou onéreux, entre ce transfert et la cession.” Sell by 31 December of the year after departure, and never lend or let the house in between, and the former main home escapes the levy. A holiday home you always kept alongside a British main residence never qualifies, which is precisely why second-home sales produce the bills examined here. Sellers who did live in the French house before returning to Britain should read our guide on selling a former French home after leaving France, where that exemption and its traps are examined in full.

B. Which social charges apply to a British seller: full schedule or 7.5% solidarity levy, and what does the treaty change?

On top of the 19 per cent come the social charges (prélèvements sociaux). The official doctrine states the principle for non-residents plainly: Non-resident individuals within income tax are brought into French social charges on the gain through the placement-income machinery of that article. Your gain is therefore charged twice at the French table: once for income tax, once for social charges, each on its own duration-relief timetable. The legal machinery sits in Article L. 136-7 of the Social Security Code, and the solidarity component in Article 235 ter of the General Tax Code, which creates, in the exact words of its second item, “Un prélèvement de solidarité sur les produits de placement mentionnés à l’article L. 136-7 du même code”, alongside a parallel levy on property income. How much of that schedule you actually bear depends on where you are insured, and Brexit gave British sellers their own answer.

The background rule comes from European coordination of social security. A person insured in one Member State should not fund the social system of another, a principle the French courts apply directly from the European Court’s De Ruyter ruling. The Cour de cassation recalled it in these terms: a person “affiliée à un régime de sécurité sociale d’un Etat membre, ne doit pas contribuer au régime de sécurité sociale d’un autre Etat membre (CJUE, 26 février 2015, De Ruyter, C-623-13, point 35)”. That is the judgment of the Second Civil Chamber of 6 June 2024, appeal number 21-23.396, published as ECLI:FR:CCASS:2024:C200518, which you can read in full at Cour de cassation, 2nd Civil Chamber, 6 June 2024, No. 21-23.396. The case itself concerned an employer’s flat-rate social contribution on a company president’s pay where the president was insured in Belgium, but the principle it restates governs your sale too: sellers insured under another European Union, European Economic Area or Swiss scheme, and outside the French compulsory system, pay only the solidarity levy at 7.5 per cent, because that levy finances the State budget rather than social security, as the official rate commentary confirms.

Brexit could have destroyed that protection for British sellers, because the United Kingdom is no longer covered by the coordination regulations. The withdrawal arrangements saved it. The tax administration confirms: Under the United Kingdom withdrawal agreements signed on 12 November 2019 and 30 December 2020, property gains realised from 1 January 2021 escape the CSG and the CRDS where the seller is affiliated to British social security, is a national or lawful resident of France, the United Kingdom or another EU Member State, and is not covered by a French compulsory scheme, as the same official rate commentary confirms. If you pay National Insurance in Britain, hold British nationality or lawful residence, and are not within the French compulsory system, your French property gain escapes the CSG and the CRDS entirely. What remains is spelled out in the next sentence: Those gains remain liable only to the 7.5 per cent solidarity levy under Article 235 ter. Only that levy remains, collected under the same assessment, control, recovery, security and penalty rules as the Article 244 bis A levy itself. Three practical consequences follow. First, bring proof of British social-security affiliation to the signing meeting: an A1 certificate, an HMRC letter, or National Insurance records, because the exemption is conditional, not automatic. Second, if you are in neither the British nor a European scheme — for example you retired early, pay voluntary contributions nowhere, and are covered by nothing — the full schedule applies, and the simulation must say so. Third, a British seller who works in France and belongs to the French system is charged the full schedule with no 7.5 per cent limitation at all.

Return to the worked example with that distinction. On the social-charge base of about 106,405 euros, a qualifying British seller insured in the United Kingdom pays only the 7.5 per cent solidarity levy, roughly 7,980 euros, alongside 8,398 euros of income tax: a total French bill near 16,378 euros on a 130,000-euro gross gain. A seller outside any qualifying scheme pays the full schedule on the same base, a dramatically heavier bill for the identical house. That single difference — proven by one affiliation document — is often worth more than any other line in the file, and it is the line most often missed when a sale is prepared from London without French advice.

The second half of the question is the treaty: having paid France, what happens in Britain? The France-United Kingdom double tax convention gives France, where the house sits, the primary right to tax gains on French immovable property, under its Article 14 on capital gains, and leaves it to the country of residence to eliminate the resulting double taxation under its Article 24. The French commentary on the convention states the mechanism in general terms: where one State may tax gains under Article 14, it is the other State, the seller’s State of residence, that must eliminate the double taxation. Applied to your sale, France taxes first under Article 244 bis A, and the United Kingdom, as your residence State, relieves the double charge by credit. The British side of that machinery is confirmed by the official guidance on selling overseas property: UK residents pay Capital Gains Tax when they dispose of overseas property, and those taxed twice may be able to claim relief. You therefore declare the French sale on your UK Self Assessment return, compute the UK gain under British rules, and claim Foreign Tax Credit Relief for the French tax attributable to the same gain, capped at the UK tax on that gain. Keep the French assessment notice, the deed showing the tax withheld, and the proof of payment: HM Revenue and Customs will want them. Note the asymmetry that surprises many sellers. The two countries measure the gain differently — different acquisition costs, different reliefs, different rates — so the credit wipes out double taxation but never promises identical treatment. Where the UK tax exceeds the French tax, a British balance remains payable in Britain. Where the French tax exceeds the UK tax, the surplus is simply unrelieved. The treaty prevents double taxation; it does not equalise the two bills.

II. What must happen on signing day, and how do you challenge the bill or the notaire?

A. Who files form 2048-IMM, when is an accredited representative compulsory, and what does the 150,000-euro threshold change?

French capital-gains tax on property is not assessed months later by letter. It is taken at the table, from the price, on the day of the final deed (acte authentique de vente). The seller’s notaire draws up the capital-gains return on official form 2048-IMM-SD, withholds the income tax, the social charges and any surtax from the available price, and pays the Treasury when the deed is registered. The standard clause in the deed, quoted by the Paris Court of Appeal, reads: “Le vendeur donne dès à présent pouvoir au notaire à l’effet de prélever sur le disponible du prix, le montant de la plus-value déterminée sur l’imprimé 2048-IMM-SD pour le verser au trésor public.” That sentence, from Paris Court of Appeal, Division 4 Chamber 13, 19 March 2024, No. 21/01462, describes every French property completion: you authorise the deduction in advance, and the money never passes through your hands. The statute behind it, Article 244 bis A, provides: “L’impôt dû en application du présent article est acquitté lors de l’enregistrement de l’acte ou, à défaut d’enregistrement, dans le mois suivant la cession, sous la responsabilité d’un représentant établi en France, accrédité par l’administration fiscale.” Payment happens at registration, under the responsibility of a representative established in France and accredited by the tax administration.

That representative is the Brexit trap in the procedure. Because the United Kingdom is neither in the European Union nor in the European Economic Area, a British seller living in Britain must in principle appoint an accredited tax representative (représentant fiscal accrédité) who stands responsible for the tax. Article 244 bis A exempts only sellers established inside the protected circle: “L’obligation de désigner un représentant fiscal ne s’applique pas lorsque le cédant est domicilié, établi ou constitué dans un Etat membre de l’Union européenne ou dans un autre Etat partie à l’accord sur l’Espace économique européen ayant conclu avec la France une convention d’assistance administrative en vue de lutter contre la fraude et l’évasion fiscales ainsi qu’une convention d’assistance mutuelle en matière de recouvrement de l’impôt.” Before Brexit, a Manchester seller needed nobody; after Brexit, the same seller needs an accredited professional, typically a specialist firm, whose accreditation depends on a clean tax record, compliance with filing and payment duties for those it represents, and financial guarantees. The representative’s fee is yours to pay, and the appointment must be arranged before completion, because without it the land registry can refuse the deed. Your notaire cannot fill the role: the commentary recalls that regulated professions are incompatible with tax representation, and names the profession of notaire first. Anyone who tells you the notaire’s signature covers both functions is mistaken.

One automatic way out exists, and it turns entirely on price. The administration confirms an automatic exemption: sales at or below 150,000 euros need no representative, assessed seller by seller, so each co-owner of a jointly held house is tested on their own share, as the official representative commentary confirms. Two refinements matter. For a married couple, whatever the matrimonial regime, and for civil partners taxed jointly, the couple counts as one seller against the whole price. And the threshold looks only at the price stated in the deed for the building and its rights: That 150,000-euro test looks solely at the price stated in the deed for the building or the rights. The commentary adds that an agency commission included in the stated price is not subtracted for the threshold test, even though it can reduce the taxable gain itself. A Dordogne cottage selling at 290,000 euros therefore needs a representative; the same cottage selling at 140,000 euros does not. Check the deed price, not your net proceeds.

The reason the simulation must come before the preliminary contract (compromis de vente), not after, is written in two court decisions. In Bordeaux, a seller marketed a building plot that had become constructible, accepted an offer at 326,000 euros on 30 June 2021, signed the preliminary contract on 28 July 2021 and completed on 1 April 2022. The tax then arrived: a tax bill totalling 84,158 euros, which the seller said she learned of, with calculations she disputed, only once she could no longer withdraw from the sale. Eighty-four thousand euros of taxes, communicated too late to walk away. The court held the notaire liable for failing to advise on the fiscal consequences of the sale and awarded 25,247 euros for the lost chance of abandoning the project. That is the judgment of the Bordeaux Tribunal judiciaire, First Civil Chamber, 18 March 2025, case number 23/00043, readable at Bordeaux Tribunal judiciaire, 1st Civil Chamber, 18 March 2025, No. 23/00043. Twenty-five thousand euros for the lost chance of giving up the sale — a figure that measures exactly what timely advice is worth.

The Paris decision makes the same point from the other side of the table. Spouses who had bought land in 1998, built a house, and sold house and land in February 2016 for 210,000 euros declared a taxable gain of 25,257 euros and paid 16,012 euros in duties, then turned against the professionals over the handling of the returns. The Court of Appeal, in its judgment of 19 March 2024, held that the notarial office “a commis une faute de nature à engager sa responsabilité civile professionnelle” — committed a fault engaging its professional liability — and ordered compensation with interest. The lesson for a British seller is direct. Insist, before signing the compromis, on a written tax simulation showing the gross gain, each relief, the income tax, each social charge with the rate applied and why, the surtax test, the withholding, and whether a representative is needed. If the simulation arrives only with the draft final deed, the Bordeaux seller’s story shows what that delay costs. And keep every computation: a challenge or a professional-liability claim is built on paper, not on recollection.

B. How do you challenge an excessive bill or a notaire who never warned you: claim, court action and UK credit?

Start with the arithmetic, because most excessive bills are arithmetic before they are law. Recompute the gain from the two deeds: the sale price in the final deed against the purchase price in the acquisition deed, with the statutory adjustments. Verify the ownership period in full years from the acquisition date, not from the year you started using the house, and apply the two different relief timetables — twenty-two years for income tax, thirty for social charges — exactly as quoted in section I.A. Test the 50,000-euro surtax threshold against the net taxable gain, seller by seller where the house is co-owned. Check the social-charge rate against your affiliation evidence: the 7.5 per cent solidarity-only treatment requires British social-security affiliation, British nationality or lawful residence, and no French compulsory cover, all three together, so a missing A1 certificate or an unexamined French part-time contract can explain a full-schedule charge. Finally, confirm that the treaty was respected: France taxes the French property, and Britain relieves, not the reverse. Each of these checks maps to one of the texts quoted above, which means each can be put to the tax office in precise terms rather than as a general complaint.

The formal challenge in France begins with a claim to the administration. Article L. 190 of the Tax Procedures Book (Livre des procédures fiscales) sends claims seeking “soit la réparation d’erreurs commises dans l’assiette ou le calcul des impositions, soit le bénéfice d’un droit résultant d’une disposition législative” to the contentious courts — that is, it defines the claims a judge can hear, from wrong bases and wrong computations to rights the statute grants and the assessment denied. In practice you file a written réclamation (formal claim) with the non-residents tax office that collected the levy, identifying the assessment, stating the correct figures with evidence, and asking for discharge or reduction. File it as soon as the error is spotted: time limits in tax litigation are strict, and the administration’s express or implied rejection opens the route to the administrative court (tribunal administratif), where the two-month rhythm of administrative litigation applies. Article R. 421-1 of the Administrative Justice Code provides that proceedings must be brought “dans les deux mois à partir de la notification ou de la publication de la décision attaquée” — within two months of notification or publication of the contested decision. A late application fails whatever its merits, so the calendar matters as much as the computation. Before the court, the available arguments follow the structure of this guide: wrong gain, wrong relief period, wrong social-charge rate for a qualifying British affiliate, surtax wrongly applied below the threshold or to the wrong seller, representative wrongly imposed at or below 150,000 euros, or treaty misapplied. Each argument needs its exhibit: deeds, affiliation proof, the 2048-IMM return, the assessment, the claim and its rejection.

Where the loss comes not from the assessment but from the professional — the simulation that never came, the 84,158 euros discovered after the point of no return — the action lies against the notaire, as the Bordeaux and Paris decisions show. The claim is for breach of the duty to advise and to inform, measured as the lost chance of acting differently: walking away, renegotiating the price, restructuring the sale, or simply waiting for a further year of relief. Preserve the chronology: when each computation was communicated, in what form, and what decision it preceded. The preliminary contract date is usually decisive, because once the compromis binds you, the chance the court values has already been lost. A liability claim and a tax challenge can run in parallel, and often should: the tax claim reduces the bill, while the professional claim repairs what an excessive but lawful bill, properly announced, would have allowed you to avoid.

Do not neglect the British end of the file. If the French bill is reduced on claim or in court, the UK computation changes too, because the Foreign Tax Credit Relief follows the French tax actually and finally due. An amended French assessment should be reported to HM Revenue and Customs with a corrected position, and any overpaid UK tax reclaimed within British time limits. Conversely, a French refusal that you intend to litigate does not suspend the UK reporting obligation: declare, claim the credit available on the facts as they stand, and adjust when the French outcome becomes final. Running both files together — French challenge, British return — is the only way to keep the treaty promise of single taxation intact.

Conclusion

Selling a French second home from Britain after Brexit means accepting French taxation first and organising everything around it. The 19 per cent levy falls on the gain measured from deed to deed, duration relief removes it over twenty-two years for income tax and thirty for social charges, the surtax bites above 50,000 euros of net taxable gain, and social charges collapse to the 7.5 per cent solidarity levy for sellers who prove British affiliation outside the French system. The price decides the procedure: above 150,000 euros a British seller appoints an accredited representative, and the notaire withholds and pays the tax at registration in every case. The treaty then moves the file to Britain, where the gain is declared again and the French tax credited, without ever promising the two bills will match. Two disciplines protect you. Get the written simulation before the preliminary contract, with every rate justified, and challenge quickly and precisely when the figures are wrong — to the tax office within its deadlines, to the administrative court within two months of rejection, and to HM Revenue and Customs with corrected figures when France moves. Prepared that way, the sale remains what it should be: the profitable end of years of French holidays, not an expensive lesson in foreign procedure.