You bought the stone cottage in the Dordogne in 2014, when a pound still bought patience and a swimming pool felt like a reasonable retirement plan. Eleven years later the children have scattered, the roof needs attention, and you have decided to sell up from your home in Kent and crystallise the gain. This is the moment many British owners discover that France taxes the sale first, taxes it at the notaire’s desk before you ever see the money, and applies a set of rules that changed quietly but significantly when Britain left the European Union. The headline rate is a 19 per cent levy on the gain, plus social levies, plus in some cases a surtax on large gains — and two valuable exemptions that your French or German neighbours still enjoy are closed to you because your passport is now a third-country passport.

None of this means the bill is whatever the notaire’s computer says it is. French property gains are computed under a precise statutory method — sale price minus purchase price, minus documented costs, minus a taper relief that grows with every year you hold the property — and each step of that calculation can be checked, evidenced and, where the administration has got it wrong, challenged. The double tax treaty between France and the United Kingdom then decides which country taxes what, and it gives France the first bite while obliging Britain to grant a credit so the same gain is not taxed twice. This article explains, in order, how France works out the taxable gain on a British seller, what Brexit changed to the social levies and the exemptions, what happens on completion day at the notaire’s office, and how to dispute a bill you believe is wrong. If you are still at the stage of owning and running the house year to year, our guide to French property tax for British second-home owners covers the annual charges; if you have just arrived, start with the arrival formalities every British newcomer must complete.

I. How France taxes the gain when the seller lives in Britain

A. The 19 per cent levy and the taper relief that rewards patience

French tax law starts from a simple proposition. Capital gains realised by individuals on the sale for consideration of built or unbuilt property are liable to income tax under a dedicated statutory regime. Article 150 U of the General Tax Code (Code général des impôts) states it in these terms: “les plus-values réalisées par les personnes physiques ou les sociétés ou groupements qui relèvent des articles 8 à 8 ter , lors de la cession à titre onéreux de biens immobiliers bâtis ou non bâtis ou de droits relatifs à ces biens, sont passibles de l’impôt sur le revenu dans les conditions prévues aux articles 150 V à 150 VH” (Article 150 U, Code général des impôts, Légifrance). That wording covers residents and non-residents alike, because the Code elsewhere treats gains on French-sited property as French-source income: “Sont considérés comme revenus de source française : a. Les revenus d’immeubles sis en France ou de droits relatifs à ces immeubles” (Article 164 B, Code général des impôts, Légifrance). Living in Tunbridge Wells rather than Toulouse therefore does not take you outside the French charge; it puts you inside a special non-resident collection mechanism, examined below, but the gain itself is computed under the same domestic rules.

For an individual seller who is not fiscally domiciled in France — domicile being defined by Article 4 B of the Code, which looks at where your home, your principal place of residence and your professional activity are situated (Article 4 B, Code général des impôts, Légifrance) — the tax takes the form of a withholding-style levy called the prélèvement. Article 244 bis A of the Code provides that the gains in question are “soumises à un prélèvement selon les taux fixés au III bis”, and its rate paragraph is explicit: “Toutefois, 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 %” (Article 244 bis A, Code général des impôts, Légifrance). Nineteen per cent is therefore the income-tax slice of every British individual seller’s bill, and the French tax administration confirms that this rate applies whatever the seller’s country of residence (impots.gouv.fr, international individuals, real-estate gains).

Nineteen per cent of what, though? The taxable gain — the plus-value imposable — is the sale price minus the purchase price, with both sides of that subtraction adjustable in the seller’s favour if the paperwork exists. On the purchase side, the acquisition price may be increased by the genuine purchase costs: registration duties or VAT paid on acquisition, notaire’s fees, and agency commission where it was borne by the buyer. In practice the administration accepts either the evidenced actual amount or a flat-rate allowance (forfait) of 7.5 per cent of the purchase price, and the seller takes whichever is higher. Building, extension and renovation works carried out by a registered firm and supported by invoices may then be added, either at their evidenced cost or, once the property has been held for more than five years, at a flat 15 per cent of the purchase price without any invoice at all. Because British owners frequently extend and modernise old rural houses, the choice between evidenced costs and the 15 per cent forfait is often the single most valuable decision in the whole computation, and it should be modelled both ways before the sale completes, while invoices can still be chased from long-forgotten artisans.

From that gross gain the Code then deducts a holding-period allowance — the abattement pour durée de détention — which is where patience is directly rewarded. Article 150 VC of the Code provides: “La plus-value brute réalisée sur les biens ou droits mentionnés aux articles 150 U , 150 UB et 150 UC est réduite d’un abattement fixé à : – 6 % pour chaque année de détention au-delà de la cinquième ; – 4 % au titre de la vingt-deuxième année de détention” (Article 150 VC, Code général des impôts, Légifrance). Six per cent per year from the sixth year plus the final four points means the income-tax slice of the gain disappears entirely after twenty-two years of ownership. The administration’s English-language guidance confirms the practical result: a full exemption from the income-tax levy for property held for more than 22 years (service-public.gouv.fr, Income tax — Real estate capital gains). A cottage bought in 2003 and sold in 2026 therefore bears no income-tax levy at all, however large the headline profit — though the social levies follow a slower timetable, as the next section explains.

One further charge can apply on top, and British sellers of character houses in the south should check it early. Article 1609 nonies G of the 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 ou les sociétés ou groupements qui relèvent des articles 8 à 8 ter et dans celles prévues à l’article 244 bis A par les contribuables non domiciliés fiscalement en France assujettis à l’impôt sur le revenu”, expressly including non-resident sellers within its scope. “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”, on a sliding scale from 2 per cent up to 6 per cent for taxable gains above 260,000 euros (Article 1609 nonies G, Code général des impôts, Légifrance). The surtax does not apply to building land, it is calculated by the notaire on the same form as the main levy, and it is the reason a back-of-the-envelope “19 per cent of my profit” estimate can understate the real bill by several thousand euros on a high-gain sale.

A worked illustration helps. Suppose you bought for 180,000 euros in 2014, paid 15,000 euros in acquisition costs, spent 40,000 euros on invoiced structural works, and sell for 320,000 euros in 2026 after twelve years. The gross gain is 320,000 minus 180,000 minus 15,000 minus 40,000, or 85,000 euros. Twelve years of ownership gives seven years of taper at 6 per cent — 42 per cent — leaving a taxable gain of 49,300 euros. The 19 per cent levy is about 9,367 euros, and because the taxable gain sits just below 50,000 euros, no surtax is due. Change the sale price to 340,000 euros and the taxable gain crosses the surtax threshold; change the evidence for the works and the 15 per cent forfait may beat the invoices. Every figure in that chain — price, costs, dates, allowances — is verifiable from documents you hold, which is precisely why errors at the notaire’s desk are worth challenging rather than absorbing.

B. Social levies after Brexit: the 17.2 per cent charge and the British 7.5 per cent exception

Alongside the income-tax levy, every sale bears the prélèvements sociaux, the social levies that fund French welfare and debt repayment. The administration states the headline position bluntly: the gain is also subject to social levies at the overall rate of 17.2 per cent (impots.gouv.fr, international individuals, real-estate gains). The statutory foundation is Article L. 136-6 of the Social Security Code (Code de la sécurité sociale), which brings within the contribution base “e) Des plus-values, gains en capital et profits soumis à l’impôt sur le revenu” — capital gains subject to income tax (Article L. 136-6, Code de la sécurité sociale, Légifrance). For a British seller affiliated to the French social security system — for example, a second-home owner who moved to France, joined the PUMA health system and pays French contributions — that 17.2 per cent applies in full, on the gain after a slower taper than the income-tax one: full exemption from social levies arrives only after thirty years of ownership, as the administration confirms: a parallel exemption from social levies once ownership exceeds 30 years (service-public.gouv.fr, Income tax — Real estate capital gains). The eight-year gap between the income-tax exemption and the social-levies exemption is a trap for owners who assume that twenty-two years of ownership wipes the slate entirely clean.

For British sellers who stayed affiliated to the British system — state pensioners on an S1, early retirees on private cover, anyone who never joined the French scheme — Brexit produced a specific and surprisingly favourable settlement. Since 2019, persons affiliated to a compulsory social security scheme other than the French one, within the European Economic Area or Switzerland, have been exempt from the CSG and CRDS components of the levies. And the administration expressly extends that treatment across the Channel: that although the United Kingdom left the European Union on 1 January 2021, British residents keep the benefit of this CSG and CRDS exemption — although the United Kingdom left the European Union on 1 January 2021, British residents continue to benefit from this CSG and CRDS exemption. The price of that exemption is a residual solidarity levy: a residual solidarity levy at the rate of 7.5 per cent — the income remains subject to a solidarity levy at the rate of 7.5 per cent (impots.gouv.fr, international individuals, real-estate gains). In practice, then, a British-resident seller affiliated to National Insurance pays 19 per cent plus 7.5 per cent — 26.5 per cent all-in before any surtax — rather than the 36.2 per cent borne by a French-affiliated seller, a Brexit outcome that runs in Britain’s favour and should be verified on every completion statement.

That favourable treatment is not automatic in the sense of being applied blindly: the exemption turns on genuine affiliation to a compulsory scheme, and the notaire will want evidence — an S1 certificate, a National Insurance record, or equivalent proof of cover — before applying the 7.5 per cent rate instead of 17.2 per cent. Where the seller splits time between systems, holds a French pension alongside a British one, or moved affiliation mid-ownership, the file needs to establish which scheme covered the seller at the relevant date, and gaps in the paper trail are the most common reason the full rate is applied by default. Because the difference between 17.2 and 7.5 per cent on a six-figure gain runs into five figures, assembling that evidence before completion day is one of the highest-value tasks in the whole sale.

It is worth understanding why the levies look like this at all. A decade ago the Court of Justice of the European Union held that France could not charge CSG and CRDS — contributions legally classified as social security charges under EU coordination rules — on persons already affiliated to another Member State’s scheme, and France rewrote its legislation in response, replacing those charges for non-affiliated sellers with the solidarity levy. The post-Brexit settlement for Britons is the descendant of that litigation: the exemption survived the end of free movement by administrative decision, confirmed on the impots.gouv.fr page quoted above. That history matters for one practical reason — it shows these rules move. Rates, thresholds and the scope of the British exception have all changed within the last ten years, so any advice predating 2021, and any internet forum summary that does not distinguish the 19 per cent levy from the social levies, should be treated as suspect until checked against the current texts.

II. Completion day, surviving exemptions and fighting an excessive bill

A. The notaire, form 2048-IMM and the accredited tax representative

Unlike income tax, which you declare and pay months after the event, French property gains are collected at the moment of sale, by the notaire, before the price reaches you. The conveyancing notaire (notaire) — the public officer who authenticates the deed, the acte de vente — computes the gain, withholds the levy, the social charges and any surtax from the purchase price, and remits them to the Treasury when the deed is registered. The return on which everything is computed is form 2048-IMM-SD, and the administration’s English guidance notes that form 2048-IMM-SD, whose computation table is in practice completed by the notaire (service-public.gouv.fr, Income tax — Real estate capital gains). For the seller sitting in Britain, completion day is therefore largely a paper exercise conducted by others — which makes it all the more important to approve the 2048-IMM computation in draft, line by line, before the deed is signed, because money withheld in error is far harder to recover than money correctly computed in the first place.

The statutory machinery behind that withholding is Article 150 VG of the Code: “Une déclaration, conforme à un modèle établi par l’administration, retrace les éléments servant à la liquidation de l’impôt sur le revenu afférent à la plus-value ainsi que, le cas échéant, les éléments servant à la liquidation de l’impôt sur le revenu afférent à la plus-value en report d’imposition et détermine le montant total de l’impôt dû au titre de la cession réalisée.” For sales evidenced by a formal deed, that return “Elle est déposée : 1° Pour les cessions des biens mentionnés à l’article 150 U constatées par un acte, à l’appui de la réquisition de publier, de la demande d’inscription sur le livre foncier de Mayotte ou de la présentation à l’enregistrement”, and it is filed on pain of refusal of registration: “Cette déclaration est remise sous peine de refus du dépôt ou de la formalité de l’enregistrement” (Article 150 VG, Code général des impôts, Légifrance). In plain terms, no 2048-IMM means no registered deed, and no registered deed means the buyer does not legally own the house — so the return is not optional paperwork but the key that completes the transfer.

British sellers face one additional Brexit consequence at this stage: the accredited tax representative, the représentant fiscal accrédité. Article 244 bis A provides that “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”, and it sets accreditation conditions — clean tax record, compliance with filing duties, financial guarantees — breach of which causes withdrawal of the accreditation: “Le non-respect de l’une de ces conditions entraîne le retrait de l’accréditation” (Article 244 bis A, Code général des impôts, Légifrance). The Code then dispenses certain sellers from appointing one: “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” having the relevant assistance conventions with France. Read that list carefully and the Brexit effect is obvious — the United Kingdom appears nowhere in it. A British-resident seller must therefore in principle sell through an accredited representative established in France, whose fee — typically a fraction of a per cent of the price with a minimum charge — is a genuine Brexit cost of selling, and whose appointment should be arranged weeks before completion, not discovered at the signing table.

Practical preparation repays itself several times over. Before completion, assemble the original purchase deed (titre de propriété) showing the price, the settlement statement from the purchase showing duties and fees, every invoice for works with proof of payment, the S1 or National Insurance evidence for the social-levy rate, and proof of the dates of ownership for the taper. Send them to the notaire early and ask for the draft 2048-IMM with the taper computation shown year by year. Check the exchange-rate treatment if any figure was originally in sterling, check that the correct ownership dates drive the abatement, check that the 7.5 per cent solidarity rate rather than 17.2 per cent has been applied where you qualify, and check the surtax line whenever the taxable gain approaches 50,000 euros. Each of these is a documented, checkable figure — and each is a ground of challenge if it is wrong.

B. Which exemptions survive Brexit, what Britain charges, and how to challenge the bill

Start with the exemption British sellers most often assume they still have, and do not. Article 150 U of the Code grants non-resident sellers an exemption of up to 150,000 euros of net taxable gain on a French dwelling — but only where the seller “est une personne physique, non résidente de France, ressortissante d’un Etat membre de l’Union européenne ou d’un autre Etat partie à l’accord sur l’Espace économique européen”, and only where the seller was continuously domiciled in France for at least two years at some point before the sale: “à la condition qu’il ait été fiscalement domicilié en France de manière continue pendant au moins deux ans à un moment quelconque antérieurement à la cession” (Article 150 U, Code général des impôts, Légifrance). The nationality condition is a hard Brexit cut-off: a British passport holder selling today cannot claim the 150,000-euro shelter, however long they once lived in France. The administration’s international page restates the same condition, limiting the relief to nationals of EU and EEA states (impots.gouv.fr, international individuals, real-estate gains). Any pre-2021 advice suggesting otherwise is out of date, and any completion statement that claims the exemption for a British seller is wrong in the seller’s favour today but would be corrected — with interest — on audit.

A second exemption, for the home that was your main residence when you left France, is drafted more broadly but fenced with strict conditions. Article 244 bis A exempts the sale of the property that constituted the seller’s main residence in France at the date of the transfer of the tax domicile abroad, provided the new residence is in an EU Member State or in a State that has concluded both an administrative-assistance convention and a recovery-assistance convention with France of equivalent scope — and provided, crucially, that the sale occurs no later than 31 December of the year following the departure year and that the property was not made available to third parties, free or for payment, between departure and sale: the exemption applies “à la double condition que 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” (Article 244 bis A, Code général des impôts, Légifrance). Note the asymmetry the Code itself creates: the non-resident computation rules of Article 150 U apply in full to EU and EEA nationals, while this departure exemption looks instead to the destination State’s conventions — a distinction that keeps litigation alive and makes the treaty analysis below essential rather than decorative.

The exemptions that need no nationality test remain fully available. The sale of your actual main residence — the home you genuinely occupy for most of the year at the date of sale — is entirely exempt, a point worth remembering for British sellers who moved back into the French house before selling it. Property held for more than twenty-two years is exempt from the income-tax levy, and property held for more than thirty years from the social levies too. And where the property passes not by sale but by death, different rules apply altogether — see our guide to wills, English-law choice and the forced heirship reserve, and, for the family vehicle many British owners use to hold the house, our analysis of the SCI for British families, since selling shares in a property company is taxed under a different mechanism from selling the bricks themselves.

Then comes the British side of the equation. France gets the first bite because the treaty says so: Article 14(1) of the France–United Kingdom convention of 19 June 2008 provides that gains from the disposal of immovable property situated in one of the two States are taxable in that State, which is why a British resident selling a French house always settles the French levy first (BOFiP, France–United Kingdom tax convention commentary). But a British resident seller is also within the UK capital gains net, because HM Revenue & Customs states plainly: that a person resident in the UK pays Capital Gains Tax when disposing of overseas property, adding that that tax may also be due where the gain arises, with relief available where double taxation occurs (GOV.UK, Tax when you sell property: selling overseas property). The treaty resolves the overlap by credit: Article 24 of the same convention treats French tax properly charged under its rules as a credit against any United Kingdom tax computed on the same gains, so the French levy is set against the UK bill rather than added to it (BOFiP, France–United Kingdom tax convention commentary). In practice you report the disposal on a UK Self Assessment return, compute the UK gain under UK rules — which differ from the French computation, notably on costs, reliefs and the annual exempt amount — and set the French levy against the UK bill, paying HMRC only any excess. Keep the 2048-IMM, the completion statement and proof of payment: HMRC will want them, and the deadlines on the two sides of the Channel do not align.

If the French bill itself looks wrong, challenge follows the ordinary tax-dispute path, and the starting point is almost always the file rather than the forum. First, obtain the full computation: the signed 2048-IMM, the notaire’s completion statement (décompte), and the registration receipt showing what was actually remitted. Compare each line against the documents you hold — purchase price, costs, works evidence, ownership dates, taper arithmetic, the social-levy rate applied, the surtax threshold. The most frequent errors are undocumented choices made under time pressure: the flat-rate allowances applied where evidenced actuals would have been higher, or lower; the 17.2 per cent social rate applied to a seller who qualified for 7.5 per cent for want of an S1 on the file; the taper counted from the wrong acquisition date where the property was inherited or gifted; the surtax triggered by a taxable gain a few hundred euros over the threshold that better cost evidence would have pulled back below it. Where the error is the notaire’s computation and the deed is recent, a corrected computation can sometimes be regularised through the notaire and the registration office without formal litigation — act quickly, because registration entries harden with time.

Where the administration maintains the assessment, the formal route is a written claim (réclamation) to the tax office that collected the levy, setting out the facts, the computation you defend, and the documentary evidence, followed — if the claim is rejected expressly or by silence — by an appeal to the administrative court (tribunal administratif) within the statutory time limit. Time limits in French tax litigation are short and strict: as a rule, claims must be filed by 31 December of the second year following collection, and missing the deadline extinguishes the claim however meritorious. Frame the claim around verifiable figures and quoted statutory wording — the taper percentages of Article 150 VC, the 19 per cent rate and representative provisions of Article 244 bis A, the exemption conditions of Article 150 U — rather than general complaints about fairness, because French tax judges decide on texts and evidence. And preserve everything: the purchase deed, the sale deed, the 2048-IMM, the S1, the invoices, the correspondence with the notaire. In a dispute about a computation, the party with the complete file usually wins.

Conclusion

Selling a French house from Britain means accepting that France taxes first: a 19 per cent levy on a statutorily computed gain, social levies at 17.2 per cent or — for British-affiliated sellers who prove it — a 7.5 per cent solidarity charge, and a surtax where the taxable gain exceeds 50,000 euros. Brexit closed the 150,000-euro ex-resident exemption to British passport holders and imposed the accredited tax representative on British-resident sellers, while leaving the taper reliefs, the main-residence exemption and the CSG-CRDS settlement for Britons intact. The treaty then hands Britain a secondary charge softened by a credit for the French tax paid. Every link in that chain is a documented figure, and every documented figure can be checked before the deed is signed or challenged afterwards through a claim and, if needed, the administrative court. Model the computation early, assemble the evidence for the social-levy rate, approve the draft 2048-IMM line by line, and keep the whole file — because on a French property sale, the best dispute is the one your paperwork wins before it starts.