You live in Manchester, Leeds or London. You own a stone cottage in the Dordogne, a village house in the Luberon or a flat near the port in Nice. You bought it years ago, when freedom of movement made the Channel feel narrow, and now you want to sell. Since 1 January 2021 you are no longer a European buyer or seller in the eyes of French tax law. You are a resident of a third State, and that single word changes the rate you pay, the reliefs you can claim and the paperwork your buyer and your notaire (the French public officer who authenticates conveyances) must complete before the price reaches your account.

The good news is that the system is mechanical once you understand it. France taxes the gain first, because the property stands on French soil. The United Kingdom taxes you again as a British resident on your worldwide gains, then relieves the double charge through a credit for the French tax. The French levy is collected at completion, out of the sale price, through a return your notaire files. Mistakes therefore surface late, when the money has already moved, and correcting them means challenging an assessment or pursuing the professional who got the analysis wrong. This guide walks through each stage: how the French gain is computed and at what rate for a British seller after Brexit, which exemptions survive and which one Brexit removed, what is filed on the day of the sale on both sides of the Channel, and how to challenge a bill or recover tax paid twice. It is written for a British reader, explains every French term at first use, and cites the exact texts and court decisions so you can check each statement.

I. How France taxes a British non-resident who sells a French house, and what you can still claim

A. How is the French plus-value calculated and at what rate for a British seller after Brexit?

The French word plus-value means capital gain: the increase in value between acquisition and sale. For a person who is not domiciled in France for tax purposes, the charging provision is article 244 bis A of the General Tax Code (Code général des impôts), which states: “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.” (article 244 bis A) In plain English: subject to tax treaties, gains on French real estate realised by non-residents suffer a withholding levy (prélèvement) at the rates set further down the same article. The cross-reference to article 164 B of the same Code matters because that article lists income treated as having a French source, including rents from buildings situated in France and, through its e bis and e ter paragraphs, the property gains themselves. If your cottage is in France, the gain has a French source and France may tax it even though you live in Britain.

The starting point of the computation is familiar. Article 150 V of the General Tax Code provides: “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.” The gross gain is the sale price minus the acquisition price paid by the seller. Each price is then adjusted: notary fees, stamp duty and genuine renovation work carried out by a registered builder increase the acquisition side, while sale costs reduce the proceeds, all within documented caps. Duration of ownership then reduces the taxable base through a statutory taper (abattement pour durée de détention): after a holding period that the tax administration applies year by year, income tax on the gain disappears entirely, while the social levies fade more slowly and vanish only at the end of a longer period. Your notaire applies this taper mechanically from your title deeds, so keep every completion statement (décompte), builder invoice and planning consent from the day you bought.

The rate is where Brexit bites. The French tax administration confirms on its official page for non-residents that a non-resident gain suffers a 19 % levy whatever the country of residence, plus social levies at the overall rate of 17.2 %. The statute itself confirms the 19 % figure for individuals: certain non-resident sellers “sont soumis au prélèvement au taux de 19 %.” (article 244 bis A) Before Brexit, European Union residents could argue for alignment with the domestic treatment; since 1 January 2021, British sellers are residents of a third State, and the Conseil d’Etat has validated the architecture. In a decision of 23 June 2022 concerning a challenge to the article 244 bis A levy, the court held that European Union law “faisait seulement obstacle à un prélèvement excédant le taux de 19 % applicable, en vertu des dispositions de l’article 200 B du code général des impôts, aux plus-values de même nature réalisées par les résidents de France, de l’Union européenne et des autres Etats parties à l’accord sur l’EEE” (Conseil d’Etat, 23 June 2022, No. 445785), and it rejected the appeal. The full decision, Conseil d’Etat, 9th chamber, 23 June 2022, No. 445785, is the authority to cite if anyone tells you the 19 % rate is negotiable. It is not, but anything above it would be.

On top of the 19 % come the social levies (prélèvements sociaux). The legal base is article L. 136-6 of the Social Security Code, which charges a contribution on asset income of persons domiciled in France and, by extension through the non-resident regime, on property gains with a French source: “Les personnes physiques fiscalement domiciliées en France au sens de l’article 4 B du code général des impôts sont assujetties à une contribution sur les revenus du patrimoine”, including “Des plus-values, gains en capital et profits soumis à l’impôt sur le revenu”. The headline rate is 17.2 %, but the composition matters enormously for a British seller. The tax administration states that persons affiliated to a compulsory social security scheme of an EEA State or Switzerland are exempt from the two largest components, the contribution sociale généralisée (CSG) and the contribution au remboursement de la dette sociale (CRDS), and it adds expressly: although the United Kingdom left the European Union on 1 January 2021, British residents keep this CSG/CRDS exemption, while the income remains subject to a 7.5 % solidarity levy. In practice, then, a British seller covered by the NHS who holds a valid S1 healthcare certificate or otherwise proves affiliation to the British scheme should see the social charge fall from 17.2 % to the 7.5 % solidarity levy, provided the proof is produced with the file. If your completion statement shows the full 17.2 %, that single line is often the first thing to challenge, and the S1 form explained in our guide to recovering social charges on British pensions is the same document that can save you here.

One further tax can apply to large gains. 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 expressly “dans celles prévues à l’article 244 bis A par les contribuables non domiciliés fiscalement en France assujettis à l’impôt sur le revenu”. The surtax bites only where the taxable gain exceeds 50,000 euros: “La taxe est due à raison des plus-values imposables d’un montant supérieur à 50 000 €”, on a sliding scale from 2 % to 6 % of the whole taxable gain. It does not apply to exempt sales or to building land. A British owner selling a Dordogne farmhouse bought cheaply in 2005 can therefore face three stacked charges on the same gain: 19 % income levy, social levies at 17.2 % or 7.5 %, and the surtax if the taxable amount tops 50,000 euros. The official service-public.fr page on property gains gives the same worked logic for residents, noting that a supplementary tax applies where the taxable gain exceeds 50,000 euros, at rates from 2 % to 6 %, computed on form 2048-IMM-SD, in practice calculated by the notaire. Ask your notaire for the 2048-IMM computation table before completion, not after, and check each line against your own deeds.

B. Can you still claim an exemption after Brexit: former main home, second home, and the relief the British lost?

Two exemptions dominate British files, and Brexit treats them very differently. The first survives. The second, for most British-only nationals, does not. Understanding which is which before you sign the preliminary contract (compromis de vente) determines whether you keep tens of thousands of euros or hand them to the Treasury for no reason.

The surviving relief covers the person who lived in the French house as their main home, moved back to Britain, then sold shortly afterwards. Article 244 bis A itself provides it: the levy does not apply to the sale of the building that was the seller’s principal residence in France at the date the seller transferred their tax domicile out of France, provided the new residence sits in a European Union State or in a State that has signed with France both an administrative assistance convention against fraud and a mutual recovery assistance convention comparable to the European directive on the subject. The United Kingdom qualifies under these assistance instruments, so a move to Britain is not the obstacle. The two cumulative conditions are strict, and the statute states them exactly: “Cette exonération s’applique 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) Sell by 31 December of the year after your departure, and do not let, lend or otherwise make the property available to anyone in the meantime, not even to family rent-free and not even for a single summer season. The tax administration confirms that where these conditions are met, a qualifying exempt seller need not file the gain return at all, although the deed of sale must state the legal basis of the exemption. Useful detail: the relief extends to the property’s immediate and necessary outbuildings where they are sold at the same time, and a taxpayer who has already used a related earlier relief cannot use this one again. If you left France in March 2025, keep the house empty, and complete the sale by December 2026, the gain can be fully exempt. Miss either condition and the whole gain falls back into charge.

The relief that Brexit removed is the flat 150,000 euro allowance. Article 150 U of the General Tax Code normally exempts the sale of a principal residence, and its paragraph II, 2° extends a capped exemption to non-residents selling a French dwelling: up to 150,000 euros of net taxable gain, once per taxpayer, subject to having been continuously domiciled in France for at least two years at some point and to completing within ten years of departure. But the personal scope is closed: the administration states that it covers disposals by individuals not resident in France who are nationals of an EU Member State or another EEA State. Nationality is the test, not residence. A seller holding only British nationality no longer meets it. A dual French-British or Irish-British seller still can, which is why your notaire should ask for every passport you hold, not only the one you travel on. If your file was prepared on the assumption that the 150,000 euro shelter still applies to you as a British-only national, that assumption needs correcting before completion, because the buyer will not wait while the computation is redone.

Two recent court decisions show how these residence questions turn into real disputes at the signing table. In Nice, a seller who insisted the house sold in November 2023 had remained her main residence challenged her notaire for paying 18,655 euros of gain tax out of her proceeds on the buyer’s word that a tenant occupied the house. The tribunal judiciaire of Nice, 3rd civil chamber, 2 July 2026, RG 24/01760, examined the occupation evidence, found the professional had failed in its duty, and ordered: “CONDAMNE la SAS Dius Difius à payer à [K] [V] la somme de 18 655 euros au titre du préjudice financier, avec intérêts au taux légal à compter de la date de délivrance de l’exploit introductif d’instance”, plus 1,500 euros for non-pecuniary loss and 2,500 euros under article 700 of the Code of Civil Procedure. Read the full ruling at Tribunal judiciaire de Nice, 2 July 2026, No. 24/01760. The lesson for a British seller is practical: if you claim main-home treatment, assemble utility bills, tax notices, insurance and sworn statements proving continuous personal occupation before the file goes to the notaire, and never let the other side’s conveyancer settle the point over the telephone.

The mirror image appears in a Versailles case where non-resident sellers tried to use a different domestic relief, the reinvestment exemption of article 150 U, II, 1° bis, by earmarking 400,000 euros of the price for a future main home in France. The declaration prepared for the sellers showed a sale price of only 460,000 euros out of a true 860,000 euros, until the buyer’s notaire pointed out “que cette exonération fiscale n’était pas applicable, faute pour les associés de la SCI d’avoir la qualité de résidents fiscaux en France”, so that the taxable gain “s’établissait ainsi à 102 496 euros au lieu de 54 027 euros”. The cour d’appel of Versailles, 1st chamber, 25 July 2023, RG 21/03288, ultimately rejected the damages claim against the sellers’ notaire because the alleged loss of a chance to reorganise was never proved, holding “INFIRME le jugement en toutes ses dispositions” and “REJETTE les demandes d’indemnisation et de capitalisation des intérêts de la SCI Nicolas Mathieu”. See Cour d’appel de Versailles, 25 July 2023, No. 21/03288. For a British reader the warning is blunt: domestic reinvestment reliefs designed for French residents do not stretch to cover a non-resident simply because the money will later be spent in France. Claim only the relief whose statutory conditions you meet on the day of completion, and evidence each one.

II. How the sale is filed on both sides of the Channel, and how to challenge a wrong bill

A. What does the notaire file on completion day, and what does Britain require from you?

In France, the tax is not paid months later with an annual return. It is taken at the source, on the day the authentic deed (acte authentique) is signed. Article 244 bis A states the mechanism without ambiguity: “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.” (article 244 bis A) In practice your notaire prepares the capital gains return on form 2048-IMM, deducts the levy and the social charges from the price, pays the Treasury within the month, and remits only the balance to you. The administration’s guidance confirms that the 2048-IMM table computes the surtax too, and that in practice calculated by the notaire. Because the money moves first and arguments come later, every British seller should demand three documents at least a week before completion: the draft 2048-IMM with each adjustment identified, the taper calculation with the acquisition date and each expense proved, and the social-levy breakdown showing whether the 7.5 % solidarity rate or the full 17.2 % has been applied. If the S1 certificate evidencing your NHS affiliation is missing from the file, the higher rate will be applied by default, and recovering the difference means a formal claim rather than a telephone correction.

Many British sellers also need an accredited tax representative (représentant fiscal accrédité). The statute requires payment under the responsibility of an accredited representative established in France (article 244 bis A), and adds that only a person meeting strict integrity conditions may be accredited, including no serious or repeated tax offences and none of the disqualifying commercial sanctions in the preceding three years. The official guidance summarised on service-public.fr is direct: a non-resident whose gain is taxable must appoint a tax representative, who must hold administration accreditation and offer guarantees. Exemptions exist for low-value sales and for sellers resident in the EU or EEA, but a British resident selling a French house above the thresholds should budget for this appointment. The representative guarantees the tax to the Treasury, so reputable firms charge a fee proportionate to the risk and will ask for the same evidence your notaire needs. Appoint them when the compromis is signed, not the week of completion, because without their signature the file cannot be registered.

France taxes first because the treaty gives it the first right. The France–United Kingdom double tax convention of 19 June 2008, commented by the tax administration in BOI-INT-CVB-GBR-10, the France–United Kingdom convention of 19 June 2008, follows the standard OECD pattern for immovable property: gains from the alienation of real estate situated in one State may be taxed in that State. Your French cottage is therefore taxable in France without any need to argue about where you live, and the United Kingdom, as your State of residence, relieves the resulting double taxation by credit rather than by exemption. On the British side the position is stated plainly on GOV.UK: residents pay Capital Gains Tax when disposing of overseas property, may also face tax where the gain arose, and may claim relief if taxed twice. See GOV.UK, Tax when you sell property: selling overseas property, with the detailed credit mechanics in Helpsheet HS263, Relief for Foreign Tax Paid. Concretely, a British resident reports the French sale on the UK Self Assessment foreign pages, computes the UK gain under UK rules (which differ on costs, currency and reliefs such as private residence relief), and claims Foreign Tax Credit Relief for the French levy up to the amount of UK tax on the same gain. Keep the French 2048-IMM, the completion statement and proof of payment: HMRC will ask for them. Where the French tax exceeds the UK tax on the same gain, the excess is not refunded by Britain; where the UK tax is higher, you pay the difference. Neither the treaty nor Brexit removes this two-step charge, so model both taxes before you accept an offer, not after the notaire has distributed the price.

A final filing point concerns timing and proof. The French payment deadline runs from registration of the deed, and the UK Self Assessment deadline follows the normal 31 January cycle, with the UK 60-day reporting regime for the UK tax on the disposal running in parallel for British residents disposing of overseas property only through the Self Assessment framework where applicable to the year. The exact UK deadline depends on your residence position and whether split-year treatment applies, so confirm it with your British accountant as soon as the compromis is signed. On the French side, store the authenticated deed, the 2048-IMM, the representative’s certificate, the S1 or NHS affiliation proof, and every invoice relied upon, for at least six years. If a reassessment (proposition de rectification) arrives, these papers are your defence; without them, even a correct computation is hard to sustain. Readers dealing with the reverse movement, a British resident selling a British house while living in France, will find the treaty-credit mechanics explained from the other direction in our guide to selling a UK house as a French resident, and those holding through a company should read our analysis of the family SCI before selling, since an SCI changes both the computation and the representative question.

B. How do you challenge a French assessment, a 17.2 % charge, or tax paid twice?

Start with the most common error: social levies charged at 17.2 % on a seller who should have paid 7.5 %. The administration’s own page grants British residents the CSG/CRDS exemption where affiliation to a compulsory British scheme is proved, with only the 7.5 % solidarity levy remaining. If your completion statement shows the full rate, the remedy is a formal tax claim (réclamation contentieuse) to the non-residents tax office (Service des impôts des particuliers non-résidents), attaching the S1 certificate or NHS affiliation evidence, the 2048-IMM and the deed. File within the statutory claim period running from the assessment or payment, send it by recorded delivery or through your online account (espace particulier), and ask expressly for discharge (dégrèvement) of the excess with default interest. Where the office refuses expressly or stays silent for six months, the refusal can be taken to the administrative tribunal (tribunal administratif), and from there to the administrative court of appeal, exactly the route travelled in the Conseil d’Etat decision cited above, where the taxpayer challenged the 244 bis A levy through the Nice tribunal, the Marseille appeal court and finally the Conseil d’Etat. That taxpayer lost on the 19 % rate itself, but the procedural path is the one to follow for a claim that is genuinely well founded, such as a wrongly applied 17.2 %.

The second battleground is the computation: taper misapplied, deductible work rejected, wrong acquisition price, or an exemption refused. Here the file, not the rhetoric, decides. Reconstruct the chain of title from the original acquisition deed, prove each euro of works with builder invoices showing the property address, and check the holding period date by date. If the notaire refused the former-main-home exemption on the ground that the house was let between departure and sale, test that finding against your own evidence of free disposal; if the administration accepted the exemption but the buyer’s conveyancer imposed tax, the Nice ruling shows the remedy may lie against the professional rather than the Treasury. Conversely, the Versailles ruling shows courts will not indemnify a seller whose alternative plan existed only in words: the sellers there could not show “ils avaient l’intention, la possibilité financière et matérielle ou l’opportunité de différer la vente et de s’organiser pour fixer leur résidence fiscale en France préalablement à la vente” (Versailles, 25 July 2023, No. 21/03288), so the claim failed even though the initial declaration had been wrong. A challenge needs a counterfactual you can prove, such as a dated letter deferring completion or evidence that the relief conditions were in fact met.

The third line of attack concerns the notaire personally. French law sets the bar high and states it memorably. The Cour de cassation, 1st civil chamber, 28 May 2025, No. 23-18.737, quashing a Toulouse appeal ruling about undisclosed additional taxes on building land, held: “Le notaire est tenu d’informer et d’éclairer les parties, de manière complète et circonstanciée, sur la portée et les effets, notamment quant aux incidences fiscales, de l’acte auquel il prête son concours.” The court added that where a tax burden is determinable in principle and amount from the preliminary contract onwards, “le notaire doit son conseil spontanément avant l’engagement définitif des parties”. Read the ruling at Cour de cassation, 1st civil chamber, 28 May 2025, No. 23-18.737. Applied to a British seller, this means the notaire must flag, before the compromis becomes binding, the 19 % levy, the applicable social rate, the surtax above 50,000 euros, the need for a tax representative, and any exemption deadline such as the 31 December cut-off for the former main home. The Bordeaux tribunal quantified what silence costs: where a notaire failed to warn a seller about the gain tax before the preliminary contract, the court assessed the lost chance of walking away at 30 % and ordered: “CONDAMNE Maître [J] [U] à payer à Mme [H] [I] la somme de 25.247 euros en réparation de la perte de chance subie du fait du manquement à l’obligation de conseil sur la fiscalité sur la plus value applicable à la cession de sa parcelle” (Bordeaux, 18 March 2025, No. 23/00043), plus 3,000 euros under article 700. If your notaire presented the tax figures hours before the authentic deed, when withdrawal was contractually impossible, that chronology is the core of a liability claim, to be raised first with the professional’s insurer and then, if needed, before the civil court.

Double taxation itself is resolved through the credit, not through exemption. If HMRC refuses Foreign Tax Credit Relief, check the usual stumbling points: the French tax must be computed on the same gain and must have been finally paid, the claim must identify the correct treaty article, and exchange-rate conversions must be consistent. If France and Britain genuinely tax the same gain and the credit still leaves a residue because of rate differences, that residue is the lawful price of the treaty bargain, not an error to litigate. But where the same euro of gain is taxed twice because one administration mischaracterised the facts, for instance by treating an exempt former main home as a taxable second home, correct the characterisation at source first: a French discharge automatically reduces the British credit base and the whole problem collapses. Work the files in order, France first, Britain second, and keep both administrations looking at the same deed, the same dates and the same computation. Heirs who inherit rather than sell face a different tax with different allowances, covered in our guide to French inheritance tax on a French house, and owners keeping the property should check each autumn whether the annual bill is right by reading our guide to the 2026 taxe foncière.

Conclusion

A British resident selling a French house after Brexit faces a clear, mechanical sequence. France taxes the gain at source under article 244 bis A at 19 %, plus social levies at 17.2 % or, with proper NHS affiliation proof, the 7.5 % solidarity levy, plus a 2 % to 6 % surtax above 50,000 euros of taxable gain. The former-main-home exemption survives for sellers who complete by 31 December of the year after departure and keep the property entirely at their own disposal; the 150,000 euro non-resident allowance, reserved to EU and EEA nationals, is in practice lost to British-only sellers. The notaire collects the tax through form 2048-IMM under the responsibility of an accredited representative, and Britain then taxes the same disposal with credit relief for the French charge. Check the 2048-IMM before completion, prove your social-security position with an S1, diary the exemption deadlines, and keep every deed and invoice. If the bill is wrong, claim the discharge in France first through a formal réclamation and then the tribunal route, adjust the British return second, and where the professional failed to warn you before you were bound, pursue the notaire on the duty the Cour de cassation restated in May 2025. Prepared this way, the sale of a much-loved French house becomes an administrative exercise rather than a dispute, and the proceeds reach Britain with only the tax the law truly requires.

Need a quick opinion on your case.

If you are selling a French house as a British resident and want the 2048-IMM, the social-levy rate or an exemption checked before completion, our firm offers a telephone consultation within 48 hours with an advocate of the chambers. Call +33 6 46 60 58 22 or write through our contact page, sending the compromis, the acquisition deed and any S1 certificate you hold. Early review costs far less than a reassessment.