You bought a house in the Dordogne or an apartment in Paris years ago, and now you want to sell. Since Brexit, the French tax bill on that sale follows rules that were not written with British owners in mind, and several of the reliefs your French neighbours take for granted are closed to you. The good news is that the core of the system is stable and readable: France taxes the gain made on French soil, at a flat 19% levy for a British individual seller, plus French social charges at an overall rate of 17.2%, with a precise scale of reliefs that shrink the taxable gain the longer you have owned the property. The bad news is that two valuable exemptions — the €150,000 allowance reserved for non-residents and the total exemption for a main home sold shortly after leaving France — come with nationality and timing conditions that now catch out British sellers. This guide works through the calculation step by step, explains which exemptions a British passport still opens and which it closes, and sets out exactly how to check the notaire’s figures and how to challenge an assessment you believe is wrong, with the statute texts and the court decisions that decide these cases.
I. How much French capital gains tax will you pay when you sell your French house as a British seller after Brexit?
A. How the 19% levy, the social charges and the holding-period reliefs combine on your sale price
Start with the basic mechanism. When you are not fiscally domiciled in France — that is, when France is not your tax home under article 4 B of the Code général des impôts, the French tax code — the gain on your French property is not added to a French income tax return the way a resident’s gain would be. It is caught by a separate withholding-style levy, the prélèvement of article 244 bis A of the Code général des impôts. The computation of the gain itself follows the same domestic rules as for residents, but the tax is collected at the signature of the sale deed, through your notaire, under the responsibility of a tax representative established in France. For an individual seller, the rate question was settled plainly by the statute: “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 %”. The French tax administration confirms the point in its guidance for non-residents: the levy applies at 19% regardless of the country where you live. Your British passport does not raise that rate.
The 19% is only the first layer. The gain is also subject to French social charges — the prélèvements sociaux — at an overall rate of 17.2%. Here Brexit produced a result that surprises many sellers in a pleasant way. Since gains realised from 1 January 2019, persons affiliated to a compulsory social security scheme other than the French scheme, in a country of the European Economic Area or Switzerland, are exonerated from the two largest components, the CSG and the CRDS. The administration states expressly that, although the United Kingdom left the European Union on 1 January 2021, British residents keep this CSG and CRDS exoneration. The gain remains, however, subject to a solidarity charge at the rate of 7.5%. In practice, then, a British resident seller pays 19% income levy plus 7.5% solidarity charge on the taxable gain, with the balance of the 17.2% falling away where the British social security affiliation is properly evidenced — typically through an S1 form or proof of National Insurance coverage produced to the notaire before completion.
Before any rate is applied, the gain itself must be measured, and this is where most disputes begin. The taxable gain is the sale price minus the acquisition price, with defined adjustments on each side. The acquisition price is increased by purchase costs — either the actual costs evidenced by invoices or a flat 7.5% allowance — and by the cost of construction, reconstruction, extension or improvement works, evidenced by invoices from registered businesses, with a flat 15% allowance available only after five years of ownership. The sale price is reduced by the costs of disposal such as agency fees borne by the seller. Every missing invoice is money lost: works done by friends, paid cash without paperwork, or carried out by a British builder who never issued a proper French-language facture will simply not count.
The measured gain is then reduced by holding-period reliefs, and the official scale published on service-public.fr works differently for the 19% levy and for the social charges. For income tax purposes the relief runs at 6% per year from the sixth to the twenty-first year of ownership, then 4% for the twenty-second year, with total exemption beyond twenty-two years. For social charges the relief runs at 1.65% per year from the sixth to the twenty-first year, 1.6% for the twenty-second year, and 9% per year from the twenty-third to the thirtieth year, with total exemption only beyond thirty years. Take a concrete illustration on a €10,000 gain realised after ten years of ownership, the administration’s own example: the income tax relief is 6% for each year from the sixth to the tenth, hence 30%, leaving €7,000 taxable, while the social charge relief is 1.65% for each of those five years, hence 8.25%, leaving €9,175 subject to the charges. After twenty-five years the same €10,000 gain is fully exempt from income tax, and the social charge relief totals 55% — 26.4% for years six to twenty-one, 1.6% for year twenty-two, and 27% for years twenty-three to twenty-five — leaving only €4,500 chargeable. After thirty years, nothing remains taxable at all.
One further layer applies to large gains: the surtax on high property gains created by article 1609 nonies G of the Code général des impôts. It bites only where the taxable gain exceeds €50,000 — “La taxe est due à raison des plus-values imposables d’un montant supérieur à 50 000 €” — and then applies to the whole gain on a sliding scale from 2% to 6%. A taxable gain of €80,000 attracts 2%, or €1,600; a gain of €130,000 attracts 3%, or €3,900; and anything above €260,000 attracts 6%. Small sales are spared twice over: gains on disposals for €15,000 or less are entirely outside the tax under article 150 U, and the surtax only starts at €50,000 of taxable gain.
Put the layers together on a realistic British file. You bought a village house for €300,000 in 2012, you sell for €450,000 in 2026, agency fees of €10,000 are borne by you as seller, and you can evidence €25,000 of qualifying works. The gross gain is €450,000 minus €300,000 minus €10,000, or €140,000, reduced by the €25,000 of works to €115,000. After fourteen years of ownership the income tax relief is 6% for nine years — years six to fourteen — hence 54%, leaving a taxable base of €52,900. The 19% levy is about €10,050, the 7.5% solidarity charge about €3,970, and the surtax at 2% on a gain between €50,001 and €60,000 adds roughly €1,060. The total French bill is near €15,000 on a €140,000 economic profit — provided every figure survives the checks described below.
B. Why the €150,000 non-resident exemption and the departure exemption now treat British sellers differently
The computation above assumes no exemption applies. Three exemptions matter to British sellers, and Brexit changed the reach of two of them. The first is the simplest and survives intact: the sale of your main home is totally exempt. Article 150 U of the Code général des impôts removes from the tax the buildings that constitute “la résidence principale du cédant au jour de la cession” — the property that is your main home on the day of the sale. If you still live in France in the house you are selling as your genuine main residence, you pay nothing, whatever your nationality. The trap, confirmed by the Conseil d’État on 14 March 2025 in decision no. 474943, is that only genuine, effective occupation counts. The sellers had bought land, built a house, claimed to have moved their main residence there for a few months, then sold; the court of appeal had refused the exemption by reasoning about their intentions, and the Conseil d’État quashed that reasoning with a clear rule: the lower court had only to assess “les conditions dans lesquelles ils avaient occupé effectivement ce bien” — the conditions in which they had actually lived in the property — and by judging intentions instead it had committed an error of law. A main home claimed on paper but never truly lived in will not survive a tax audit, and the same decision shows that losing the income tax exemption drags the social charges and the surtax back in with it, since the reassessed sellers were charged with all three.
The second exemption covers the British seller who lived in France, moved back to the United Kingdom, and sells the former French main home shortly afterwards. Article 244 bis A provides that the levy does not apply to the sale of the building that was the seller’s main residence in France on the date the seller transferred the tax domicile out of France, provided the new home is in a European Union Member State or in a State that has assistance conventions with France — a condition the United Kingdom satisfies — and provided two cumulative conditions are met: “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 you left, and do not let, lend or otherwise make the house available to anyone in between — not even to family rent-free, and not through a holiday letting — and the gain escapes the French levy entirely. Miss either condition and the exemption is lost for good; the statute offers no discretion and no partial relief. Note the interaction the administration stresses: a seller who uses this departure exemption cannot later claim the €150,000 non-resident exemption on the same property.
The third exemption is the one Brexit closed. Article 150 U, II, 2° grants non-resident individuals an exemption of up to €150,000 of net taxable gain on the sale of a dwelling in France, but only to sellers who are “ressortissante d’un Etat membre de l’Union européenne ou d’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”, and only “dans la limite d’une résidence par contribuable et de 150 000 € de plus-value nette imposable”. The condition is one of nationality, not of residence: since 1 January 2021 a British citizen is no longer a national of a European Union Member State, and the United Kingdom is not party to the European Economic Area agreement. A British passport holder selling a French second home therefore cannot claim this €150,000 shelter, even if the seller lived in France for years before leaving and even if the seller now lives in another European Union country such as Spain or Ireland. The remaining conditions — having been fiscally domiciled in France continuously for at least two years at some point before the sale, and selling no later than 31 December of the tenth year after leaving, or with no time limit where the seller has had free disposal of the property since 1 January of the year before the sale — simply never come into play for a British national. The service-public.fr English guidance confirms the nationality lock in plain terms: the €150,000 relief requires the seller to hold the nationality of a European Union country, with two years of past French residence. This is the single most expensive Brexit consequence in the French property tax system for second-home owners, and it is routinely missed by British sellers who remember the pre-2021 position.
A neighbouring relief deserves a warning of its own. Article 150 U, II, 1° bis exempts the first sale of a dwelling other than the main residence where the seller has not owned a main residence in the previous four years — but the Conseil d’État held on 12 February 2020 in decision no. 415475 that “par le 1° du paragraphe II de l’article 244 bis A du même code, aux seuls 2° à 9° du paragraphe II de cet article 150 U a pour effet d’exclure les personnes physiques non fiscalement domiciliées en France lors de la cession de leur bien immobilier du bénéfice de l’exonération prévue en faveur de la première cession d’un logement autre que la résidence principale”. A non-resident at the date of sale cannot use the first-cession exemption at all. In that same decision the Conseil d’État gave Swiss sellers a lifeline from their bilateral treaty, holding that its equal-treatment clause means gains “sont imposées dans les mêmes conditions que le bénéficiaire soit résident fiscal français ou suisse” — taxed on the same terms whether the recipient is French or Swiss resident. British sellers should not assume an equivalent reading of the France–United Kingdom treaty of 19 June 2008 without advice: the treaty certainly gives France, as the State where the property sits, the right to tax the gain, and any claim to equal treatment with French residents must be built article by article, not assumed.
Finally, the British side of the Channel does not disappear once the French bill is paid. The GOV.UK guidance for overseas property states the United Kingdom position bluntly: a person resident in the United Kingdom pays Capital Gains Tax when disposing of overseas property. It adds that tax may also be due in the country where the gain was made, and that relief can be claimed where the same gain is taxed twice. A British seller who has returned to the United Kingdom and is again United Kingdom resident will therefore normally declare the French sale to HM Revenue and Customs, compute the United Kingdom gain under United Kingdom rules — which differ, notably on acquisition costs, works and reliefs — and credit the French tax against the United Kingdom bill under the treaty, so that the French levy is not simply added on top. A seller who remains French resident has no United Kingdom bill on the French house beyond the French one, but must still report correctly in France, including through the first-tax-return and property-declaration obligations that apply to newcomers and owners. The two computations are independent, the two deadlines are independent, and the treaty relief must be actively claimed — it is never automatic.
II. How do you challenge a French capital gains tax bill or a refused exemption after the sale?
A. What to check on the notaire’s 2048-IMM calculation before and just after completion
In France the capital gains tax is not assessed months later by an inspector. It is computed, declared on the printed form 2048-IMM, and paid at the signing of the authentic deed, by your notaire, out of the sale price. That makes the weeks before completion the decisive moment: once the deed is signed and the levy paid, an error can still be corrected, but only through a formal claim against the administration, with interest running on nobody’s side but yours. Ask your notaire for the draft 2048-IMM computation at least two weeks before the signing date, and work through five checks that decide nearly every British file.
First, the acquisition price and its additions. The notaire starts from the price stated in your original purchase deed, converted where necessary, and adds purchase costs and works. Produce the original deed of acquisition, the itemised statement of purchase costs, and every works invoice issued by a registered business showing the property address, the nature of the work and VAT. Where invoices are missing, the flat allowances — 7.5% of the purchase price for acquisition costs, 15% of the purchase price for works after five years of ownership — apply automatically, so compute both routes and keep the better one. Do not let the file go forward with round-number works estimates or with invoices made out to a different property: the tax administration disallows them as a matter of course.
Second, the holding period and the relief table. The relief clock runs from the date of acquisition to the date of sale, and a single quarter can move a file across a threshold year. Verify the exact dates on both deeds, confirm that the 6%, 4%, 1.65%, 1.6% and 9% annual rates have been applied to the correct years, and confirm that the income tax base and the social charge base have been relieved separately — a frequent source of six-figure errors is a spreadsheet that applies the income tax timetable to the social charges. Recompute the surtax line independently: confirm the taxable gain truly exceeds €50,000 and that the correct 2% to 6% band has been applied to the whole gain, not to the slice above the threshold.
Third, the exemption claimed, if any. If the deed states that the property was your main residence, the statement must be true on the day of sale, in the sense of genuine occupation recognised by the Conseil d’État in its 14 March 2025 decision no. 474943. If you rely on the departure exemption of article 244 bis A, evidence the date of transfer of your tax domicile out of France, the absence of any letting or free occupation since, and the sale deadline of 31 December of the following year. If anyone suggests the €150,000 non-resident exemption, stop: as shown above, a British national cannot claim it, and a deed that claims it will produce a reassessment with late-payment interest and penalties.
Fourth, the social charge position. Give the notaire, before completion, your S1 form or equivalent proof of affiliation to the United Kingdom social security system so that the CSG and CRDS exoneration is applied and only the 7.5% solidarity charge is levied. Files prepared without that proof are routinely taxed at the full 17.2%, and recovering the difference afterwards requires a separate claim supported by affiliation evidence covering the date of the sale.
Fifth, the tax representative. Since Brexit, a British seller whose gain is taxable must in principle act through a représentant fiscal — an accredited representative established in France who signs the declaration and guarantees the tax. The statute keeps three doors out of that obligation, restated in the administration’s guidance: the seller is a national of a European Union or European Economic Area State with the relevant conventions, the sale price does not exceed €150,000, or the gain is fully exempt taking the holding period into account. A British seller above €150,000 of sale price with a taxable gain needs the representative, whose fee is a normal sale cost worth budgeting from the start. A deed signed without the required representative exposes the file to challenge on regularity alone.
The notaire’s responsibility for these statements is not theoretical. On 22 September 2021 the Cour de cassation, First Civil Chamber, appeal no. 19-23.506, held a notaire liable where the deed wrongly described the property as the seller’s main residence. The Court restated the governing rule — “le notaire rédacteur d’acte doit mentionner les coordonnées des parties, conformément aux éléments dont il a connaissance” — and quashed the appeal court’s discharge of the notaires precisely because “il résultait de ces constatations que les notaires avaient connaissance avant la vente de la fausseté de l’affirmation selon laquelle le bien constituait à cette date la résidence principale” of the seller. A notaire who knows the exemption statement is false and signs anyway answers for the resulting reassessment. For the seller, the lesson runs both ways: never press a notaire to insert a statement you know to be untrue, and keep every email and attestation showing what the notaire knew, because that paper trail decides any later action for professional negligence.
B. How to file a formal claim, use the treaty and take the case to the tax judge
Where the deed is already signed and you consider the bill wrong — a refused exemption, a miscomputed relief, social charges levied at 17.2% despite your S1, or a surtax band misapplied — the remedy is a formal claim, the réclamation contentieuse, addressed to the tax office that handles non-residents. Draft it as a legal pleading, not as a complaint letter. Identify the assessment by deed date, property address and the 2048-IMM reference, state precisely the discharge or reduction sought in euros, and attach every supporting document: the acquisition deed, the works invoices, the proof of occupation or of the date of departure from France, the S1 or National Insurance evidence, and the treaty provisions relied on. Keep proof of dispatch and of receipt, because the administration’s silence after six months counts as an implied rejection that opens the next stage, and the time limits run from the assessment and from each decision — check the deadline printed on the tax notice itself and diary it immediately, since a late claim fails whatever its merits.
Four lines of argument win most British cases. The computation line attacks the figures: wrong acquisition price, disallowed invoices that were in fact qualifying, holding-period years miscounted, income tax and social charge timetables confused, or the surtax applied below €50,000 of taxable gain. Recompute the file independently and put the corrected 2048-IMM arithmetic in the claim as an exhibit; inspectors settle clean arithmetic far more readily than bare assertions. The occupation line replays the main-residence question with evidence rather than adjectives: council tax and taxe d’habitation records, utility bills across the seasons, school and medical records, and neighbours’ attestations, assembled to show effective occupation within the meaning of the Conseil d’État’s 2025 decision no. 474943. The exemption line enforces the departure conditions of article 244 bis A to the letter — sale by 31 December of the year after departure, no disposal to third parties in between — or demonstrates, with dated evidence, that each condition was in fact met where the administration presumed otherwise.
The treaty and European law line is the most technical and often the most valuable. Where the administration has applied a heavier charge to you than to a French resident in a comparable situation, the Conseil d’État’s 23 June 2022 decision no. 445785 sets the method: “il convient de comparer la charge fiscale supportée respectivement par ce contribuable et un contribuable résident de France placé dans une situation comparable”, and where the non-resident was effectively treated worse, the tax must be reduced “dans la mesure nécessaire au rétablissement d’une équivalence de traitement”. In that case the court accepted that European Union law “faisait seulement obstacle à un prélèvement excédant le taux de 19 %” applicable to residents under article 200 B — “Les plus-values réalisées dans les conditions prévues aux articles 150 U à 150 UC sont imposées au taux forfaitaire de 19 %” — so the excess over 19% was struck down and the 19% itself stood. A British seller taxed above the resident benchmark on a comparable gain can therefore demand a reduction to the resident level, while a British seller already taxed at 19% cannot use that route to go below it. Treaty arguments then take over for what European law no longer covers: the France–United Kingdom treaty’s allocation of taxing rights over immovable property gains, and any equal-treatment clause, construed article by article as the Conseil d’État construed the Franco-Swiss clause in its 12 February 2020 decision no. 415475.
If the claim is rejected expressly or by silence, the file moves to the administrative court — the tribunal administratif — within the appeal deadline stated on the rejection. The court rehears the whole file: figures, occupation evidence, exemption conditions and treaty law. Ask in the alternative for full discharge and, failing that, for partial reduction, so that a judge convinced on only one point can still cut the bill. Where the administration’s position turns on the validity of a statutory provision itself, a priority question of constitutionality can be raised through the judge, as past challenges to the non-resident levy show. And where the fault lies with the deed rather than with the assessment — a notaire who inserted a false exemption statement, or who failed to apply reliefs the file plainly supported — a parallel action for professional negligence before the civil courts, on the foundation of the Cour de cassation’s 22 September 2021 ruling no. 19-23.506, recovers what the tax judge cannot. Readers dealing with the income side of their French property, rather than its sale, will find the parallel mechanics explained in our guide to rental income tax for British landlords, and newcomers wrestling with residence and first filings in our guide to the first French tax return.
Conclusion
Selling a French house as a British owner after Brexit is a computation before it is a dispute: a 19% levy on the correctly measured gain, a 7.5% solidarity charge where British social security affiliation is proved, holding-period reliefs that erase income tax after twenty-two years and social charges after thirty, and a surtax that starts only above €50,000. The exemptions reward the seller who plans ahead — a genuine main residence sold as such, a departure sale completed by 31 December of the following year with no letting in between — and punish the seller who assumes the old rules survive: the €150,000 non-resident shelter is reserved by its own text to European Union and European Economic Area nationals, and the first-cession relief is closed to anyone non-resident on the day of sale. Build the file before the deed with invoices, dates and affiliation proof, check the notaire’s 2048-IMM line by line, and where the bill is wrong, claim promptly, compute precisely and plead the treaty article by article, with the decisions above as your authorities. Prepared sellers in this system pay the right amount and not a euro more; unprepared ones pay for somebody else’s assumptions.
Need a quick opinion on your case
You are selling a French house as a British owner and want to check the capital gains calculation, an exemption or a reassessment before the deadline expires. Our firm offers a telephone consultation within 48 hours with a lawyer of the firm to review your deeds, your 2048-IMM computation and your supporting evidence. First telephone consultation: 80 EUR including VAT. Call +33 6 46 60 58 22, or write via our contact page with the sale price, the acquisition date and the assessment or draft computation you have received.