You live in Britain, pay your tax to HMRC, and vote in the United Kingdom — yet the stone cottage in the Dordogne, the village house near Carcassonne or the small flat in Nice that you bought years ago as a holiday home is about to be sold, and the French taxman claims the first slice of the profit. That shock is normal: since Brexit, British owners who are fully resident in the United Kingdom remain fully taxable in France on the capital gain realised on a French second home, at French rates, under French calculation rules, with French filing duties completed on the day of the sale itself. The good news is that the system is mechanical and therefore checkable: a 19% levy on the gain, social charges with a specific British post-Brexit treatment, a possible surtax above 50,000 euros of taxable gain, yearly relief that grows with the length of ownership, and a double tax treaty that lets the French tax be credited against the British bill. The bad news is that two Brexit traps catch sellers every month: the 150,000-euro second-home exemption reserved for European Union and European Economic Area nationals no longer covers British citizens, and the appointment of a French tax representative, once a formality most Europeans could skip, is now compulsory for most British sellers. This guide explains how France taxes your sale when you are resident in Britain, how the taxable gain is worked out and reduced over time, what must be filed and paid at completion, how the United Kingdom taxes the same gain with credit for the French tax, and how to challenge an excessive French assessment within the proper deadlines and before the proper courts.
I. How France taxes a British seller who never lived in the French house
A. At what rate is your gain taxed when you are resident in Britain?
The starting point is that French tax residence and British tax residence are decided by different tests, and living full-time in the United Kingdom makes you a non-resident for French tax purposes. Article 4 B of the French General Tax Code (Code général des impôts, the main French tax statute) provides that: Sont considérées comme ayant leur domicile fiscal en France au sens de l’article 4 A : a. Les personnes qui ont en France leur foyer ou le lieu de leur séjour principal
— in plain English, your French tax home (domicile fiscal) is where your household or your main place of stay is. If your home, your family life and your daily presence are in Britain, you are not fiscally domiciled in France, even if you own a French holiday home and spend several weeks a year there. That classification as a non-resident does not protect the gain: Article 164 B of the same Code lists the French-source income of non-residents and expressly covers Les plus-values mentionnées aux articles 150 U, 150 UB et 150 UC, lorsqu’elles sont relatives : 1° A des biens immobiliers situés en France ou à des droits relatifs à ces biens
— capital gains on buildings situated in France. The mechanism is then set by Article 244 bis A of the Code: 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.
And the persons concerned include, in the words of the statute: Sont soumis au prélèvement mentionné au 1 : a) Les personnes physiques qui ne sont pas fiscalement domiciliées en France au sens de l’article 4 B
— a physical person who is not fiscally domiciled in France. A British seller living in Manchester, Bristol or Edinburgh therefore falls squarely inside the French charge on the sale of a French second home: Article 4 B of the General Tax Code, Article 164 B of the General Tax Code and Article 244 bis A of the General Tax Code.
The international treaty confirms that France has the first right to tax. Article 14 of the France–United Kingdom double tax convention of 19 June 2008, headed capital gains, states in its first paragraph: 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 cottage is immovable property situated in France, so France may tax the gain; the treaty does not exempt you, it organises the sharing of taxing rights and the relief against double taxation, as Part II of this guide explains. The official British text of the convention is published on GOV.UK: 2008 UK and France Double Taxation Convention in force.
The rate itself is straightforward. The French tax administration states, on its official page for non-residents selling French property, that votre plus-value fera l’objet d’un prélèvement au taux de 19 %, quel que soit votre pays de résidence. Celle-ci sera également soumise aux prélèvements sociaux au taux global de 17,2%.
— the gain bears a 19% levy whatever the country of residence, plus social charges at the overall rate of 17.2%. The same page then gives British residents a precise and rather favourable clarification on those social charges: les personnes affiliées à un régime obligatoire de sécurité sociale, autre que français, au sein d’un pays de l’EEE ou de la Suisse, sont exonérées de CSG et de CRDS. Bien que le Royaume-Uni soit sorti de l’Union Européenne le 1er janvier 2021, les résidents britanniques continuent de bénéficier de cette exonération de CSG et CRDS.
The CSG (contribution sociale généralisée, the general social contribution) and the CRDS (contribution au remboursement de la dette sociale, the contribution repaying the social debt) are therefore not charged to a British resident affiliated to the British system — but the page adds immediately that Ces revenus demeurent cependant soumis à un prélèvement de solidarité au taux de 7,5%.
In practice a British seller pays 19% income levy plus a reduced social charge built around that 7.5% solidarity levy (prélèvement de solidarité), instead of the full 17.2% borne by most other sellers. This is the direct descendant of the famous de Ruyter litigation about social charges imposed on persons affiliated in another State, and the French administrative courts have applied that case law gain by gain: the Paris Administrative Court of Appeal held, for a 2013 Paris sale, that une personne qui n’est pas affiliée à la sécurité sociale en France, mais dans un autre Etat au sein duquel s’applique le règlement en cause, ne peut pas se voir réclamer le paiement de contributions qui présentent un lien direct et suffisamment pertinent avec le financement des branches de sécurité sociale en France
, before drawing the consequences for each levy in turn: Paris Administrative Court of Appeal, 18 December 2018, No 17PA03638. A twin decision concerning a sale in the 11th arrondissement of Paris the same year reached the same analytical framework: Paris Administrative Court of Appeal, 18 December 2018, No 16PA03396. The lesson for a British seller is practical rather than academic: verify line by line which social charges appear on the completion statement (décompte du notaire, the conveyancer’s account), because CSG and CRDS wrongly added to a British resident’s bill are recoverable.
Above those two layers sits a third one that surprises many sellers: the surtax on large gains. Article 1609 nonies G of the General Tax Code provides that La taxe est due à raison des plus-values imposables d’un montant supérieur à 50 000 €
— the tax applies to taxable gains above 50,000 euros — on a sliding scale from 2% to 6% of the whole taxable gain depending on the bracket, and it expressly covers gains taxed under Article 244 bis A, hence non-residents: Article 1609 nonies G of the General Tax Code. A cottage bought cheaply twenty years ago in an area that has boomed can therefore attract 19%, plus social charges, plus up to 6% surtax on the total taxable gain — which is why the calculation rules in the next section matter so much.
Two exemptions that sellers often invoke do not help a British resident disposing of a second home, and confusing them with your situation is the costliest mistake in this whole area. First, the main-home exemption: Article 150 U of the Code taxes 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
but then carves out 1° Qui constituent la résidence principale du cédant au jour de la cession
— property that is the seller’s main home on the day of sale: Article 150 U of the General Tax Code. A holiday home in which you never had your main residence cannot qualify, however long your family has loved it. Second, the 150,000-euro second-home exemption of Article 150 U, II, 2°, which the statute grants dans la limite d’une résidence par contribuable et de 150 000 € de plus-value nette imposable
, is reserved by its own wording to sellers who are nationals of a European Union Member State or of another State party to the European Economic Area agreement — and since 1 January 2021 British citizens are neither. Where the seller once lived in the French house as a main home and then left France, a different and narrower former-home relief under Article 244 bis A itself may apply within a short window after departure; that mirror situation, with its own one-year deadline and its 150,000-euro trap, is described in our companion guide for British leavers selling the old French family home, which you should read if you ever lived in the property full-time: Left France for Britain and now sell your old French home. For a pure second home owned from Britain, assume no exemption and focus on the calculation.
B. How is the taxable gain calculated and how does time reduce it?
The gross gain is deliberately simple. Article 150 V of the General Tax Code states: La plus ou moins-value brute réalisée lors de la cession de biens ou droits mentionnés aux articles 150 U à 150 UC est égale à la différence entre le prix de cession et le prix d’acquisition par le cédant.
— the gross gain is the sale price minus the purchase price paid by the seller: Article 150 V of the General Tax Code. Everything useful happens in the adjustments to those two prices before the rate is applied. On the purchase side, the official service-public.fr guide confirms that acquisition costs (frais d’acquisition, stamp duty and conveyancer’s fees) count for their proven actual amount or for a flat 7.5% of the purchase price: Frais d’acquisition (droits d’enregistrement, frais de notaire) pour leur montant réel justifié ou pour un montant forfaitaire de 7,5 % du prix d’achat
. On the same side, building works (travaux: construction, rebuilding, extension, improvement) count for their proven invoiced amount or, provided the property has been held for more than five years, for a flat 15% of the purchase price: Dépenses de travaux (construction, reconstruction, agrandissement, amélioration) sous conditions pour leur montant réel justifié ou pour un forfait de 15 % du prix d’achat, si le bien est détenu depuis plus de 5 ans
. Keep every invoice from French artisans, every planning permission and every completion certificate: a British seller who paid cash for a new roof or a pool without paperwork loses the uplift, while the neighbour with a file of invoices cuts the taxable gain substantially. On the sale side, the estate agent’s commission and the vendor’s certified costs evidenced on the completion statement reduce the price. The combination of the 7.5% acquisition flat rate and the 15% works flat rate means that a long-held property bought for 120,000 euros can easily show a purchase side above 145,000 euros before any relief for duration — a point the conveyancer’s draft computation sometimes understates when old deeds are incomplete.
Duration relief (abattement pour durée de détention, a percentage reduction that grows with the years of ownership) then applies separately to the income-tax base and to the social-charges base, on different timetables that must never be mixed up. The official table is as follows: no relief for the first five years; from the 6th to the 21st year, 6% per year off the income-tax base and 1.65% per year off the social-charges base; in the 22nd year, 4% and 1.6% respectively; beyond the 22nd year, full exemption from income tax while social charges continue to benefit from 9% per year; beyond the 30th year, exemption from both. In the administration’s own worked example, a 10,000-euro gain on property held ten years attracts un abattement sur l’impôt de 6 % par an de la 6e à la 10e année, soit 30 %
for income tax and un abattement sur les prélèvements sociaux de 1,65 % par an de la 6e à la 10e année, soit 8,25 %
for social charges; and the guide confirms the two finish lines in plain words: Vous êtes exonéré d’impôt sur la plus-value immobilière pour tout bien détenu depuis plus de 22 ans.
and La plus-value réalisée lors de la vente d’un bien détenu depuis plus de 30 ans est aussi exonérée de prélèvements sociaux.
Take a concrete British case: a cottage bought in 2008 for 150,000 euros, sold in 2026 for 260,000 euros, held eighteen years. Gross gain 110,000 euros; purchase side uplifted by 7.5% acquisition flat rate (11,250 euros) and, the property being held more than five years, 15% works flat rate (22,500 euros), giving a net gain around 76,250 euros before duration relief; thirteen years of relief at 6% cut roughly 78% off the income-tax base, while the same thirteen years at 1.65% cut about 21% off the social-charges base; the surtax then applies only if the remaining taxable gain still exceeds 50,000 euros. The arithmetic rewards patience and paperwork in equal measure, and every one of these steps should be re-performed independently rather than accepted from a single draft computation received a few days before completion.
Three calculation errors recur in British files and each is challengeable. First, the wrong starting price: an old purchase deed expressed in francs, a part-gift within the family, or a price that included furniture (movable property, meubles meublants) that should have been separated from the building price. Second, forgotten uplifts: actual acquisition fees above the 7.5% flat rate on expensive Paris or Riviera purchases where scale fees were high, or invoiced works abandoned because the invoices are in English from a British builder — an English invoice for work actually done on the French property is evidence like any other, provided payment is traceable. Third, duration miscounted: the holding period runs from the date of acquisition to the date of sale, and a conveyancer who starts the clock on the wrong deed date can cost a full yearly slice of 6%. When the completion statement (décompte) arrives, ask for the full computation schedule with each adjustment shown separately; a single bottom-line figure is not a verifiable calculation.
II. How a UK resident declares, pays and challenges the French bill
A. What has to happen on completion day: which form, who pays, which representative, and what about the British tax?
Unlike British self-assessment, the French tax on the sale is computed, declared and paid at the conveyancer’s office on completion day, through the French conveyancer known as the notaire — a public officer who authenticates the deed and collects the tax. The tax administration instructs sellers that Pour la cession de biens ou droit immobilier, vous devez remplir le formulaire 2048-IMM-SD.
— form 2048-IMM-SD is the capital-gains return for buildings — and that L’impôt dû (impôt sur le revenu et prélèvements sociaux) est versé par le notaire au moment de la vente.
In practice the notaire prepares the return, withholds the 19% levy, the social charges and any surtax from the sale proceeds, and pays the Treasury when registering the deed (enregistrement); the seller receives the net balance. Because the money leaves your hands at completion, any error must be spotted before the signing appointment, not after: once the deed is registered and the funds transferred, recovery means a formal claim rather than a simple correction. If you also receive other French income taxable in France, the gain must additionally be reported on the French supplementary return 2042-C, box 3VZ, so that it feeds the reference tax income (revenu fiscal de référence) used for various thresholds — a detail that matters for owners who also let a French property.
The second completion-day formality is the one Brexit changed most: the tax representative (représentant fiscal), an accredited person established in France who guarantees the tax and signs the return alongside the transaction. The official guidance states the principle bluntly: Si vous êtes non-résident, vous devez désigner un représentant fiscal dès lors que votre plus-value est soumise à impôt.
There are exactly three automatic dispensations: first, lorsque le cédant est domicilié, établi ou constitué dans un Etat membre de l’Union européenne (UE) ou dans un autre Etat partie à l’accord sur l’espace économique européen (EEE) ayant conclu avec la France certaines conventions d’assistance administrative (Islande et Norvège)
; second, pour les cessions dont le prix est inférieur ou égal à 150 000 €. Ce seuil s’apprécie par cédant
; third, pour les cessions bénéficiant d’une exonération de plus-value au regard tant de l’impôt sur le revenu que des prélèvements sociaux compte tenu de la durée de détention du bien (22 ans pour l’impôt sur le revenu et 30 ans pour les prélèvements sociaux).
A British seller resident in the United Kingdom meets none of the first condition’s geography since Brexit, so unless the sale price is 150,000 euros or less per seller or the property has been held long enough for full exemption, a representative must be appointed and paid for — typically an accredited company, a French bank, or the buyer if the buyer is French-resident. Files stall at the worst moment when this is discovered the week before completion; instruct the representative as soon as the asking price is set, and budget the fee. Note that neither the notaire nor a lawyer may act in that capacity for this purpose.
The British side of the same sale must not be forgotten, because the treaty gives France priority but does not give Britain nothing. GOV.UK states the domestic rule simply: You pay Capital Gains Tax when you ‘dispose of’ overseas property if you’re resident in the UK.
The same page adds that You may also have to pay tax in the country you made the gain. If you’re taxed twice, you may be able to claim relief.
The relief mechanism is Article 24 of the 2008 convention: French tax payable under the laws of France and in accordance with this Convention, whether directly or by deduction, on profits, income or chargeable gains from sources within France shall be allowed as a credit against any United Kingdom tax computed by reference to the same profits, income or chargeable gains by reference to which French tax is computed
— the French tax complying with the treaty is credited against the British tax on the same gain. Concretely, a British seller declares the French sale on the British Self Assessment foreign pages, computes the British capital gains tax under British rules (different base cost, different reliefs, different rates and annual exempt amount), and sets the French 19% levy and the French social charges attributable to the gain against that British liability, with any excess French tax unrelieved and any excess British tax payable to HMRC. Keep the French 2048-IMM return, the notaire’s completion statement and the payment receipts: HMRC will want proof of the foreign tax, and the treaty credit is only as solid as its paperwork. Timing mismatches are common, because the French tax is paid at completion while the British return follows after the tax year end; plan cash flow accordingly rather than assuming the two assessments will arrive together.
B. How do you challenge an excessive assessment: which deadline, which judge, which arguments?
Start with the document, not with the anger. Reconstruct the computation independently: sale price minus evidenced selling costs; purchase price plus acquisition fees (actual or 7.5%) plus works (invoiced or 15% flat rate after five years); duration relief applied separately to the two bases at the correct yearly percentages; surtax tested against the 50,000-euro threshold on the taxable gain; social charges tested for the British CSG/CRDS exemption with only the solidarity levy retained. The most frequent winnable points in British files are, in order: social charges levied at the full 17.2% without the British exemption; CSG or CRDS added despite affiliation to the British system; duration relief applied at the income-tax rhythm to the social-charges base or vice versa; the surtax computed on the gross gain instead of the relieved taxable gain; a purchase price taken from the wrong deed; and works discarded for want of French-language invoices. Each of these is a question of law or of fact that the claims procedure is designed to correct, and the Paris appeal decisions cited above show judges examining levy by levy rather than accepting global figures — in one case the court annulled the first judgment (Le jugement n° 1600201 du Tribunal administratif de Paris du 11 octobre 2017 est annulé.
) and put back to the taxpayer’s charge La somme de 12 249 euros, correspondant au montant des contributions et prélèvements sociaux déchargés à tort
; in the twin case concerning the rue Faidherbe sale, the same court restored La somme de 640 euros, correspondant au montant des contributions et prélèvements sociaux déchargés à tort par le Tribunal administratif de Paris
. The amounts differ, the method is identical: every levy must have its own legal basis.
Deadlines are unforgiving and run from payment, because the tax is collected at completion without a prior assessment notice (avis d’imposition). The first step is the administrative claim (réclamation contentieuse) to the tax office: Article R*196-1 of the Tax Procedures Book (Livre des procédures fiscales) requires that Pour être recevables, les réclamations relatives aux impôts autres que les impôts directs locaux et les taxes annexes à ces impôts, doivent être présentées à l’administration au plus tard le 31 décembre de la deuxième année suivant celle, selon le cas : a) De la mise en recouvrement du rôle ou de la notification d’un avis de mise en recouvrement ; b) Du versement de l’impôt contesté lorsque cet impôt n’a pas donné lieu à l’établissement d’un rôle ou à la notification d’un avis de mise en recouvrement
— for a levy paid by the notaire at completion, time runs from the payment under paragraph (b): Article R*196-1 of the Tax Procedures Book. A sale completed in 2026 must therefore be challenged by 31 December 2028, with full evidence attached: deeds, invoices, proof of British social-security affiliation, the 2048-IMM return and the completion statement. If the administration rejects the claim expressly or stays silent for six months, the dispute moves to the administrative court (tribunal administratif) of the place where the property sits, and Article R421-1 of the Administrative Justice Code (Code de justice administrative) sets the rhythm: La juridiction ne peut être saisie que par voie de recours formé contre une décision, et ce, dans les deux mois à partir de la notification ou de la publication de la décision attaquée.
— two months from notification of the rejection: Article R421-1 of the Administrative Justice Code. Appeal then lies to the administrative court of appeal, and the two Paris decisions above show that court engaging fully with the European coordination reasoning on social charges. Parallel to the French claim, revisit the British return: a French repayment obtained later reduces the foreign tax credited, so HMRC may require an amended Self Assessment; keeping both files consistent avoids trading a French victory for a British adjustment with interest.
A final practical note on evidence from Britain: French offices sometimes query English-language documents, but a British P60, an HMRC tax calculation, a National Insurance record proving affiliation, or a completion statement from an English solicitor on a related transaction are all admissible pieces of evidence — have them translated where the sums are large, keep originals, and never send your only copy. Where the file turns on a point of European coordination law after Brexit, such as the exact boundary of the solidarity levy for British residents, reasoned argument supported by the treaty text and the published case law carries more weight than bare assertion. And where the deadline is near, file the protective claim first with the evidence available and supplement it afterwards, rather than waiting for a perfect file and missing the 31 December guillotine.
Conclusion
A British resident selling a French second home after Brexit faces a French tax charge that is certain in principle but highly variable in amount: 19% on the gain, reduced social charges centred on the 7.5% solidarity levy with CSG and CRDS exempted for British affiliates, a 2%-to-6% surtax above 50,000 euros of taxable gain, and no access to either the main-home exemption or the 150,000-euro European second-home exemption. Time and paperwork are the two lawful reducers of the bill — yearly duration relief running to full income-tax exemption after twenty-two years and full social-charges exemption after thirty, acquisition and works uplifts that reward every kept invoice, and a treaty credit that prevents the same euro of gain being fully taxed twice. The procedure concentrates everything on completion day through the notaire and, for most British sellers, through a compulsory tax representative, which makes advance verification of the draft computation the decisive moment of the whole transaction. When the bill is wrong, the path is marked: an administrative claim by 31 December of the second year after payment, then the administrative court within two months, with levy-by-levy reasoning of the kind the Paris appeal court has already applied to these very charges. Prepare the file as if you will have to defend it, and the sale of the holiday home remains what it should be — a family decision, not a tax accident.