You bought a house in England years ago, you later settled in France, and now you are selling up. The sale completes in London, the money lands in your account, and for a moment everything looks simple. Then two tax administrations come knocking on the same gain. Britain taxes the sale because the house stands on English soil. France taxes the sale because you live here now and France taxes the worldwide income of its residents. Nothing in Brexit changed that double exposure: the France–United Kingdom double tax treaty of 19 June 2008 still allocates the taxing rights and still provides the mechanism that stops you paying twice. The mechanism is a tax credit, and it is capped. It equals the British tax you actually paid, but it can never exceed the French tax attributable to the same gain. If the British bill is the smaller of the two, France collects the difference. If your French calculation is wrong, or your British return is late, the difference grows with interest and penalties on both sides of the Channel. This guide explains, for a British reader living in France, where each country taxes the sale of your English house, the 60-day British deadline almost every seller misses, the French flat rate plus social charges, the exact treaty credit that prevents double tax, and how to challenge a reassessment when the administration gets the figures wrong.
I. Two countries tax the same sale: Britain first on the land, France second on the person
A. Britain taxes your English house first, within 60 days, at 18% or 24% after a £3,000 allowance
The treaty gives the United Kingdom the first word. Article 14 on capital gains provides that “Gains derived from the alienation of immovable property referred to in Article 6 and situated in a Contracting State may be taxed in that State.” Your house is immovable property situated in Britain, so Britain may tax the gain even though you live in France. That single sentence is the foundation of everything that follows: the British charge is not a mistake, it is the treaty working as written, and the remedy is never to ignore the British return but to use it as the basis of your French credit.
Leaving Britain does not take you outside British capital gains tax. The official guidance confirms that “Non-residents who dispose of a UK residential property are liable to Capital Gains Tax and, in most cases, get the annual exempt amount in the same way as UK residents.” As a French resident you are, for British purposes, generally a non-resident seller, and you are inside the charge on the same terms as someone still living in Manchester. The annual exempt amount, the tax-free allowance known as the AEA, stands at £3,000 for individuals for the 2024 to 2025, 2025 to 2026 and 2026 to 2027 tax years. Only gains above that allowance, after losses and reliefs, are charged.
The rates are the residential-property rates. The official guidance lists “18% and 24% for individuals for residential property gains”: broadly, the lower rate applies within your unused basic-rate band and the higher rate above it. Work out which slice of the gain falls in each band before you accept any figure HMRC, the British tax administration, puts to you, because the band allocation is the most common source of overpayment on the British side.
The deadline is the trap. The official instructions state that “You must report and pay any Capital Gains Tax due on UK residential property within 60 days of completing the sale of the property.” Sixty days from completion, not from exchange of contracts, not from the end of the tax year. Interest and penalties apply if you report or pay late, and the same page warns non-residents that “You must report all sales and disposals of UK property or land by the deadline, even if you have no tax to pay.” Even a sale with no British tax due still needs the return. File through a Capital Gains Tax on UK property account, keep a copy of the return, and if you are already within Self Assessment, the British annual tax return system, include the sale there as well.
One relief can remove the British bill entirely. Private Residence Relief exempts the gain on your only home while it was your main home. The official guide states: “You do not pay Capital Gains Tax when you sell (or ‘dispose of’) your home if all of the following apply:” including that “you have one home and you’ve lived in it as your main home for all the time you’ve owned it”, with no exclusive business use and grounds under 5,000 square metres. If you lived in the house for years before moving to France and then sold soon after, most or all of the gain may be relieved, with only the period after you moved out, plus any letting period, left chargeable. If you let the house after leaving, work through the letting and absence rules line by line rather than assuming the whole gain is taxed: readers who kept the property as an investment should compare this with the position of British residents declaring UK rental income in France, where the same treaty logic applies year after year.
Joint ownership changes the arithmetic but not the principle. Each owner reports their own share of the gain, each uses their own allowance and bands, and a transfer between spouses or civil partners follows its own no-gain-no-loss logic. If you gave a share to your spouse before the sale, take advice on the timing before you file, because an unplanned transfer can waste an allowance or shift a band.
B. France taxes the same gain because you live here: worldwide income, 19% flat tax and 17.2% social charges
France taxes you on the person, not on the land. Article 4 A of the French Tax Code, the code général des impôts, provides that “Les personnes qui ont en France leur domicile fiscal sont passibles de l’impôt sur le revenu en raison de l’ensemble de leurs revenus. Celles dont le domicile fiscal est situé hors de France sont passibles de cet impôt en raison de leurs seuls revenus de source française.” A person fiscally domiciled in France pays income tax on all of their income, worldwide. Your English house gain is part of that worldwide income even though the house never moved.
Domicile, the domicile fiscal, is defined broadly. Article 4 B treats as domiciled in France “Les personnes qui ont en France leur foyer ou le lieu de leur séjour principal”: persons whose household, the foyer, or whose main place of stay is in France. Working in France or centring your economic interests here points the same way. If you are unsure where you stand, the residence test is examined in detail in our guide to when a British newcomer becomes French tax resident. And the same article contains the safety valve: “Les personnes qui satisfont à l’un au moins des critères fixés aux a à c du présent 1 ne peuvent toutefois pas être considérées comme ayant leur domicile fiscal en France lorsque, par application des conventions internationales relatives aux doubles impositions, elles ne sont pas regardées comme résidentes de France.” Anyone who meets a domestic residence test but is deemed resident of the other State under a double tax treaty is not French-domiciled. If HMRC still treats you as British-resident under the treaty tie-breaker, the French charge on worldwide income falls away and the whole analysis changes, so settle residence before you compute anything.
Once French domicile is established, the gain is charged as a property gain, a plus-value immobilière. Article 150 U of the Tax Code provides that “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”: gains by individuals on the sale for consideration of built or unbuilt property are subject to income tax under the property-gains rules. The sale of your English house falls squarely inside that charge. The main-home exemption in the same article does not help you: it covers the seller’s main residence, the résidence principale, at the date of sale, and your main residence is now in France, not England.
The income-tax rate is flat. Article 200 B of the Tax Code states that “Les plus-values réalisées dans les conditions prévues aux articles 150 U à 150 UC sont imposées au taux forfaitaire de 19 %.” Gains within the property-gains regime bear a flat 19 per cent, whatever your marginal income-tax band. On top of that come the social charges, the prélèvements sociaux. Article L.136-6 of the Social Security Code provides that “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 assise sur le montant net retenu pour l’établissement de l’impôt sur le revenu”, expressly including “Des plus-values, gains en capital et profits soumis à l’impôt sur le revenu”. Your English house gain is investment income of a French-domiciled person, so it attracts the 17.2 per cent social levy, and the official public-service guide confirms in its English version that “You must pay social security contributions at the rate of 17.2%.” The headline French burden on the taxable gain is therefore 36.2 per cent before any treaty credit, which is why the credit mechanics in Part II matter so much.
Time heals the French bill. Holding relief, the abattement pour durée de détention, reduces the taxable gain year by year, and the official guide confirms total income-tax exemption for property held more than 22 years, with the social-charges exemption following for property held more than 30 years: “Capital gains realized on the sale of property held for more than 30 years are also exempt from social security contributions.” If you bought the English house decades ago, compute the relief before you panic: a long-held house may produce a French bill close to zero, leaving only the British side to manage. The detailed calculation, including acquisition costs, works and the exact yearly relief schedule, is set out on the impots.gouv.fr property-gains pages, and the figures must be recomputed in euros at the proper dates rather than copied from the British return.
A final warning for shared structures. If your English property is held through a company, a partnership interest or shares that derive their value from the house, Article 14(2) of the treaty lets the situs State tax those gains too, and French courts apply the same situs logic to transparent property vehicles. The Court of Cassation confirmed the primacy of treaty allocation for property-linked rights, recalling that “si la fortune consiste en biens immobiliers et accessoires, l’impôt ne peut être perçu que dans l’Etat contractant qui est autorisé à imposer le revenu qui provient de ces biens” (Commercial Chamber, 2 April 2025, appeal no. 23-14.568). Direct ownership keeps the analysis clean; anything layered over the house needs its own treaty characterisation before you file.
II. Paying once and fighting back: the capped treaty credit, the two returns and the challenge route
A. Declare in both countries, then claim a treaty credit that can never exceed the French tax
Declare twice, pay the higher of the two charges, and let the treaty do the netting. On the British side, the 60-day property return comes first, with Self Assessment entries to follow. On the French side, the gain goes on your annual income-tax return: Article 170 of the Tax Code provides that “En vue de l’établissement de l’impôt sur le revenu, toute personne imposable audit impôt est tenue de souscrire et de faire parvenir à l’administration une déclaration détaillée de ses revenus et bénéfices, de ses charges de famille et des autres éléments nécessaires au calcul de l’impôt sur le revenu”. In practice the foreign gain travels through the foreign-income schedules, forms 2047 and 2042, where the British tax paid is entered to support the credit. First-time filers should read our walkthrough of the first French tax return with forms 2042 and 2047 before their first deadline, because a gain omitted from the foreign schedules is the single fastest route to a reassessment.
The treaty credit is the heart of the file. Article 24 on the elimination of double taxation gives a French resident a credit against French tax for gains taxable in Britain, and for gains within Article 14 the credit equals the British tax with a ceiling: “to the amount of tax paid in the United Kingdom in accordance with the provisions of those Articles; however, such credit shall not exceed the amount of French tax attributable to such income”. Two consequences follow. First, only British tax effectively and definitively borne counts: provisional payments, penalties and interest are not creditable. Second, the credit is capped at the French tax on the same gain, so France always collects the difference when its 19 per cent plus 17.2 per cent exceeds the British 18 or 24 per cent on a differently computed base. The credit also operates only against income tax, not against the social charges, which is why the social levy often survives even when the income-tax line nets to nearly nothing.
The Conseil d’État enforces exactly this capping logic. In a 28 February 2025 decision on a French-domiciled taxpayer’s foreign property gain, the Court recorded that the taxpayers “se sont prévalus d’un crédit d’impôt conventionnel égal à l’impôt sur le revenu français correspondant, soit 313 110 euros”, that “l’administration fiscale a limité ce crédit d’impôt au montant de l’impôt américain qu’ils avaient supporté à ce même titre, soit 205 400 euros”, and it closed the case with “Article 1er : Le pourvoi du ministre de l’économie, des finances et de la souveraineté industrielle et numérique est rejeté.” (CE, 28 February 2025, no. 491788). The treaty there was the France–United States convention, but the architecture is the same as the France–United Kingdom text: credit equal to the foreign tax, capped at the French tax. Claim the full British tax, evidence it with the HMRC assessment and proof of payment, and expect the administration to test every pound of it.
Build the evidence bundle before you file, not after the reassessment arrives. You need the completion statement with the sterling price, the euro conversions at acquisition and sale dates, the acquisition deed with costs and works, the British property return with HMRC’s reference, proof of payment of the British tax, the letting history if any, and the holding-period computation for the French relief. Exchange-rate differences between the British gain and the French gain are normal because each country computes in its own currency under its own cost rules; never copy the sterling gain onto the French return. And if part of the proceeds funds a French main home, check the reinvestment exemption conditions early rather than discovering them after the two-year window has closed.
B. Challenge a second bill through a reclamation: errors, interest, penalties and the judge
When the French notice, the avis d’imposition, arrives with no credit, a reduced credit or a gain you do not recognise, the first weapon is the contentious claim, the réclamation contentieuse. Article L.190 of the Tax Procedures Book provides that “Les réclamations relatives aux impôts, contributions, droits, taxes, redevances, soultes et pénalités de toute nature, établis ou recouvrés par les agents de l’administration, relèvent de la juridiction contentieuse lorsqu’elles tendent à obtenir 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 ou réglementaire.” A denied treaty credit is precisely the benefit of a right resulting from a legislative and treaty provision, and a miscomputed gain is precisely an error in the base. File one claim per assessment, attach the bundle, and raise every ground at once: wrong residence analysis, wrong gain computation, omitted holding relief, omitted or capped credit, and social charges applied to a year or amount outside the statute.
Time limits decide more files than merits. Claims expire, and the same article channels late challenges into a two-year prescription running from collection or payment. Diary the deadline printed on each notice and file early: a perfect treaty argument filed one day late is worth nothing. If the administration stays silent, that silence becomes an implied rejection after six months and opens the road to the administrative court, the tribunal administratif; if it rejects expressly, the rejection letter sets the clock for the court application. Never let a file sleep while waiting for goodwill.
Late or short payment bleeds interest from day one. Article 1727 of the Tax Code provides that “Toute créance de nature fiscale, dont l’établissement ou le recouvrement incombe aux administrations fiscales, qui n’a pas été acquittée dans le délai légal donne lieu au versement d’un intérêt de retard.” and that “A cet intérêt s’ajoutent, le cas échéant, les sanctions prévues au présent code.” The same article spares interest where the taxpayer flagged the difficulty expressly on the return or where a genuine interpretation difficulty arose, so an honest disclosure on the French return is not only good practice but a potential shield. Ask for remission of penalties in the same claim where the file shows good faith, a first offence and prompt correction.
Courts see these files constantly, and the amounts explain why administrations fight them. In May 2026 the Paris judicial court dealt with Dutch-resident owners of French property companies reassessed for three wealth-tax years at 98,367 euros, 96,344 euros and 94,338 euros plus a 10 per cent surcharge and late interest, on a treaty-characterisation dispute over transparent property vehicles (TJ Paris, 5 May 2026, RG 24/13163). In February 2026 the Paris Court of Appeal handled a 2.4 million euro wealth-tax dispute turning on how foreign property gains feed worldwide-income computations (CA Paris, 19 February 2026, RG 23/06124). Your English-house file is smaller, but it raises the same three questions those courts answered: where the treaty puts the gain, how worldwide income absorbs it, and which published interpretation binds the administration. If the dispute exceeds what a claim can fix, the mutual agreement procedure in Article 26 of the treaty lets both administrations negotiate, and the administrative judge decides the rest on your bundle.
Conclusion
Selling your English house from France means paying tax in Britain on the land and in France on the person, then netting the two through a capped treaty credit. Britain takes its share first under Article 14, within a 60-day return that cannot be skipped even when no tax is due, at 18 or 24 per cent above a £3,000 allowance, with Private Residence Relief protecting genuine main-home years. France charges the same gain at 19 per cent plus 17.2 per cent social charges once domicile is settled, softened by holding relief that can erase the bill on a long-owned house. The treaty credit then equals the British tax actually paid but never exceeds the French tax on the gain, exactly as the Conseil d’État applied it, and the social charges usually survive the netting. File both returns on time, evidence every pound of British tax, compute the French gain separately in euros, and challenge any second bill by a documented contentious claim before the deadline expires. Done in that order, the sale costs you the higher of the two charges, never both.
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