You live in Manchester, Leeds or London. You own a holiday flat in Nice, a stone cottage in the Dordogne or a studio in Paris that you never moved into. Now you want to sell. The first question most British owners ask is whether the United Kingdom taxes the gain. The answer that matters more is that France taxes it first, at the moment of the sale, before the money ever reaches your British bank account. The France–United Kingdom double tax convention gives France, where the property stands, the first right to tax the gain. The French notaire (the public officer who authenticates every French property conveyance) deducts the French tax from the sale price on completion day. A 19% levy applies whatever your country of residence, plus social charges at 17.2%, plus in many cases a surtax of 2% to 6% on gains above €50,000. Since Brexit, a British seller living in the United Kingdom is a seller from outside the European Union, which means you must in principle appoint a représentant fiscal (an accredited tax representative resident in France) or the sale cannot proceed. The good news is that time is your best ally: after 22 years of ownership the income-tax slice disappears, and after 30 years the social-charges slice disappears too. This guide works through the full calculation, the representative mechanism, the paperwork, what to declare in Britain, and how to challenge a bill that is wrong.

I. How France taxes the sale of your French second home

A. Which tax France takes on a British seller’s gain

Start with the treaty, because it decides which country moves first. Article 14 of the France–United Kingdom convention of 19 June 2008, published by decree of 7 January 2010 and also available at its treaty commentary, provides in its first paragraph that “Les gains provenant de l’aliénation de biens immobiliers définis à l’article 6 et situés dans un Etat contractant sont imposables dans cet Etat.” In plain English: gains on the disposal of French land and buildings are taxable in France. If you hold the property through a société civile immobilière (a SCI, the non-trading French property-holding company many British families use), the second paragraph extends the same rule to shares and rights that derive most of their value from French property: they “sont imposables dans l’Etat où les biens immobiliers sont situés.” Selling the shares of your SCI is therefore taxed in France just like selling the bricks themselves. The treaty eliminates double taxation afterwards by obliging the United Kingdom to give relief, but it never deprives France of the first bite.

French domestic law then fixes the French bite. The English-language pages of the French tax administration state the rule bluntly: “your capital gain will be subject to 19% tax, regardless of your country of residence. It will also be subject to social security contributions at the overall rate of 17.2%.” The 19% is a flat levy (prélèvement) collected under article 244 bis A of the General Tax Code, not the progressive income-tax scale. The 17.2% is the overall social-charges rate. One Brexit fear can be set aside immediately: “Although the United Kingdom left the European Union on 1 January 2021, British residents continue to benefit from this exemption from CSG and CRDS.” The CSG (contribution sociale généralisée) and the CRDS (contribution au remboursement de la dette sociale), the two social charges reserved to people affiliated to the French social security system, are not charged to a seller affiliated to the British system. “However, such income remains subject to a solidarity levy at the rate of 7.5%.” In practice your 17.2% is therefore made up of charges a non-affiliated person can legally bear, including that 7.5% solidarity levy (prélèvement de solidarité). If a calculation you receive charges you the full CSG and CRDS on top, that line is worth contesting, as explained in part II.

The taxable gain itself is computed the French way, which differs from the British computation in two respects. The starting point is familiar: sale price minus acquisition cost. But the acquisition cost may be increased by a flat 7.5% allowance for purchase expenses (frais d’acquisition) without receipts, and by improvement works (travaux) only if you produce invoices from registered businesses and, for most works, the property is more than five years old. Keep every invoice from your French builder, because HM Revenue and Customs and the French administration do not recognise the same enhancements. Once the gross gain is set, the holding-period allowances (abattements pour durée de détention) apply at different speeds for the two slices of tax. The official English page of service-public.fr states the outcome first: “You are exempt from tax on real estate capital gains for any well held for more than 22 years.” And for the second slice: “Capital gains realized on the sale of property held for more than 30 years are also exempt from social security contributions.” Between acquisition and those finish lines, the yearly allowance runs at 6% per year from the 6th to the 21st year and 4% in the 22nd year for income tax, and at 1.65% per year from the 6th to the 21st year, 1.6% in the 22nd year, then 9% per year beyond the 22nd year for social charges. Nothing accrues during the first five years. A concrete example makes the mechanism tangible. Take a Dordogne cottage bought for €180,000 twelve years ago and sold today for €300,000, with no works invoices. The gross gain is €120,000 minus the 7.5% purchase allowance on €180,000 (€13,500), leaving €106,500. After twelve years, the income-tax allowance is 6% × 7 years = 42%, so the taxable base for the 19% levy is about €61,770, producing roughly €11,736. The social-charges allowance is 1.65% × 7 = 11.55%, so the base for the 17.2% is about €94,198, producing roughly €16,202. The combined French bill before surtax is therefore around €27,900 on a €120,000 real profit, and every additional year of ownership shaves both bases further.

One more layer catches larger gains. Article 1609 nonies G of the General Tax Code adds a surtax (surtaxe) on taxable gains above €50,000, and it expressly reaches non-resident sellers taxed under article 244 bis A. The article states that “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 total taxable gain, with a smoothing mechanism (décote) at each threshold: 2% between €50,001 and €60,000, 2% between €60,001 and €100,000, 3% up to €150,000, 4% up to €200,000, 5% up to €250,000 and 6% above €260,000. On the Dordogne example above, with a taxable gain near €61,770, the surtax adds roughly another €1,235. Sellers of Paris studios, where gains routinely exceed €150,000, should expect the 3% to 4% band to apply, and Côte d’Azur villas regularly fall into the 5% to 6% band. The surtax is assessed on the taxable gain as computed under articles 150 V to 150 VE, declared under the article 150 VG procedure and collected under the article 150 VF rules. It follows the same declaration and payment circuit as the main levy, described below, and the same challenge routes apply to it.

B. The reliefs that can cut the bill to zero

The most powerful relief is time itself, and British second-home owners often hold long enough to use it. Once you pass 22 years of ownership, the income-tax slice is gone entirely; once you pass 30 years, the social-charges slice is gone too, and the surtax, which is assessed on the taxable gain, collapses with it. If your purchase deed (acte d’achat) dates from the early 2000s, ask your notaire for a full holding-period simulation before accepting any estimate from an estate agent. A sale brought forward by a few months can cost thousands of euros if it falls just short of an anniversary, while waiting for the 22nd anniversary can wipe out the 19% levy in full. Duration is counted from the date of the acquisition deed to the date of the sale deed, and periods of letting, vacancy or personal use make no difference.

A second family of reliefs concerns sellers who used to live in France. Article 244 bis A I of the General Tax Code creates a full exemption for a non-resident seller on the former main home: “Article 244 bis A I of the French General Tax Code (CGI) provides for an exemption from capital gains tax for non-resident sellers on the sale of the home that was their principal residence in France before they moved abroad.” The conditions are strict and cumulative: the seller must not have made the property available to anyone between leaving France and selling, and the sale must be completed by 31 December of the year following the move. The administration adds that “These conditions are cumulative. If they are met, the exemption from capital gains tax exempts the non-resident seller from filing a capital gains tax return. The deed of sale must therefore mention the basis for the exemption.” A capped variant protects gains up to €150,000 for sellers who left longer ago, and a further extension reaches former residents who lived in France for at least two years. These leaver situations, with their exemption windows and treaty tail, are a subject of their own, covered in our companion guide for British leavers selling their former French home. The present guide addresses the opposite and more common case: the owner who always lived in Britain and sells a second home that was never a French main residence, where none of those leaver exemptions applies and the full calculation above governs.

Two practical reliefs remain available to every seller, including holiday-home owners. First, the purchase-cost uplift: the 7.5% flat allowance for acquisition expenses applies automatically, and documented works invoices increase the cost base euro for euro, subject to the five-year and invoicing conditions. Second, the one-time reinvestment relief for a first sale: a seller who does not own their main residence can, once in a lifetime, exempt the gain by reinvesting the price in a main home within two years. The official wording stresses the formality: “The exemption applies, at your request, by a mention in the deed of sale. You can benefit from this exemption only once.” The lesson is general and worth memorising for every British seller: in French conveyancing, a relief that is not written into the sale deed is a relief lost. Always instruct the notaire in writing, before completion, which exemption you claim and on which legal basis.

A short note for sellers in Paris and the Île-de-France, where a large share of British-owned second homes sits. Nothing in the national rates changes because the property is in the 7th arrondissement rather than in the Lot: the 19%, the 17.2% and the surtax are national taxes, and the same Paris notaire collects them through the same forms. What changes is the arithmetic and the paperwork around it. Paris gains are large, so the 3% to 4% surtax band is the norm rather than the exception, and the energy-performance file (diagnostic de performance énergétique, the DPE, with the energy audit for the worst-rated flats) conditions the buyer’s financing and therefore your timetable. Properties held through an SCI are frequent in Paris; remember that the treaty taxes the SCI shares in France exactly like the flat itself. Finally, if you rent the flat out between exchange and completion, keep the furnished-letting paperwork clean: our guide to British landlords’ French rental declarations explains how to avoid a letting dispute contaminating a sale.

II. Getting the sale through and fighting an excessive bill

A. The tax representative, the notaire and the forms

The single biggest post-Brexit change for British sellers is the représentant fiscal. Before 2021, a seller living in the United Kingdom was an EU seller, dispensed from appointing one. Since 1 January 2021, the United Kingdom is a third country outside the European Union and the European Economic Area, and the dispensation for EU and EEA sellers no longer covers you. The official doctrine of the French tax administration, in the current version of BOI-RFPI-PVINR-30-20, states the rule for sellers outside the Union in categorical terms: sellers who are individuals or entities, “domiciliés, établis ou constitués hors d’un État membre de l’UE” “ont l’obligation, dans tous les cas, de désigner un représentant fiscal.” In plain terms: whatever your situation, if you live in Britain you must appoint an accredited representative, who signs the capital-gains declaration alongside you and guarantees the tax to the French Treasury. Without that signature, the notaire cannot lawfully complete the sale, and transactions have been known to stall for weeks while a representative is found at the last minute. Appoint yours as soon as the compromis de vente (the preliminary sale contract) is signed, not the week before completion.

Three escape routes exist, and the administration lists them together: “Three situations allow for automatic dispensation from appointing a tax representative.” The first covers sellers in the European Union and the European Economic Area, which no longer helps a British resident. The second covers sales at a price of €150,000 or less, assessed per seller, so joint owners each benefit from their own threshold on their own share. The third covers sales where the gain is fully exempt by duration, both slices, which for most sellers means 30 years of ownership. Outside those three cases, budget for the representative’s fee, typically a five-figure euro sum on large Paris or Riviera sales, sometimes charged as a percentage of the tax secured. Who may act? An accredited company, a bank operating in France, or the buyer if the buyer is French-resident, or any other French-resident person approved by the tax office; notaires and lawyers are excluded from acting informally and must hold accreditation like anyone else. The doctrine extends the duty to companies and groupings whose tax regime mirrors the partnership-transparency rules of article 8, article 8 bis or article 8 ter of the General Tax Code, for whose disposals a representative must be appointed regardless of the partners’ own situation. Accreditation for a one-off sale is handled by the local public-finances office where the representative is established, not by the non-residents’ tax office, so allow several weeks.

On completion day the machinery is well oiled, and you should understand each moving part so you can check it. The seller and the representative sign form 2048-IMM-SD, the capital-gains return for property: “For the sale of property or property rights, form no. 2048-IMM-SD must be filled out.” The notaire then deducts the levy, the social charges and any surtax from the price and pays the Treasury directly: “When the sale is concluded, the notary pays the tax owed (income tax and social levies).” You receive the net price. If you have other French-source income, for example rent from another flat, the gain must also be reported on the annual return, form 2042-C, because “the amount of capital gains must be declared in form no. 2042 C (box 3VZ) so that it may be included in calculation of the base taxable income.” This second declaration does not tax you twice; it sets your overall French tax profile, and our walkthrough of the first French tax return with forms 2042, 2047 and 3916 shows how the treaty credit mechanism works in practice.

Then comes the British side, which surprises sellers who assumed the French deduction was the end of the story. The United Kingdom taxes its residents on worldwide gains, including gains on French property, and the French tax becomes a credit against the British bill rather than a replacement for it. The British government’s own guidance puts it simply: “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.” In practice you report the disposal on your Self Assessment return, compute the British gain under British rules (sterling values at acquisition and disposal, British annual exempt amount, British rates), and set the French tax paid against the British tax on the same gain, limited to the British tax attributable to that gain. Two mismatches routinely leave a British top-up payable. First, the exchange rate: sterling’s movement against the euro between purchase and sale can create a British gain even where the euro gain is modest. Second, the computation rules differ, so a gain reduced in France by generous holding allowances may remain fully taxable in Britain. Conversely, where the French bill exceeds the British tax on the same gain, the excess is not refunded by either country. Keep the French 2048-IMM, the completion statement (décompte) from the notaire and proof of payment: HM Revenue and Customs will ask for them before allowing the credit. One final treaty subtlety deserves a mention for sellers who left France recently: paragraph 6 of Article 14 preserves each country’s right to tax the gains of anyone who was its resident at any time during the previous six fiscal years, the treaty tail that also underpins the leaver exemptions. If you emigrated from France to Britain within the last six years, take advice on both sides before signing anything.

B. Challenging a bill that is wrong

French property tax bills for non-residents go wrong in predictable ways, and each error has a remedy. The most frequent is the social-charges line: a computation that charges the full CSG and CRDS to a seller affiliated to the British system, ignoring the exemption quoted in part I. The second is the holding allowance: wrong start date (a gift or inheritance restarts the clock differently from a purchase), missing year, or the income-tax rate applied to the social-charges base. The third is the surtax: assessed on the gross gain instead of the taxable gain after allowances, or the €150,000 threshold assessed on the whole property instead of per seller where co-owners sell distinct shares. The fourth is the representative’s or the notaire‘s omission: an exemption basis missing from the deed, which the administration then refuses to apply retrospectively. And the fifth is residence itself: a seller treated as French-resident and taxed on the worldwide scale, or a British seller wrongly denied the treaty credit. Work through the 2048-IMM line by line against the official pages and the doctrine cited in this guide before the funds leave the notaire‘s account; after payment, correction is still possible but slower.

The standard remedy is the written claim to the tax office (réclamation contentieuse), followed if necessary by an appeal to the administrative court (tribunal administratif). File the claim as soon as the error is spotted: the general time limit for contesting a personal tax runs to 31 December of the second year following collection, and missing it extinguishes the claim however obvious the error. Set out the correct computation, attach the deed, the 2048-IMM, proof of British social-security affiliation (your HMRC certificate or NHS-linked evidence of National Insurance coverage) where the CSG and CRDS are disputed, and the exchange-rate and invoice evidence where the base is disputed. The administration must answer with a reasoned decision; silence kept for six months counts as an implicit refusal, which you may then take to the court. Interest for late payment (intérêt de retard) and penalties fall away to the extent your claim succeeds, and a claim suspends enforcement only if you offer guarantees, so consider paying first and claiming back where the sums are large. Where the dispute concerns the treaty itself, for example which country may tax an SCI-share sale or how the six-year tail applies, the claim should cite the convention article and paragraph expressly; treaty arguments raised for the first time only before the court risk being ruled inadmissible.

Where the fault lies with the professionals rather than the administration, the liability route runs against them. The notaire owes sellers a duty to raise and record the correct tax treatment in the deed, and the courts enforce it. In a judgment of 19 March 2024 that every conveyancing practice should know, the Paris Court of Appeal held that a firm of notaires which had omitted the exemption wording from a 2016 sale deed, after which the tax office refused restitution, “a commis une faute de nature à engager sa responsabilité civile professionnelle,” and ordered it “à payer à Mme [Y] [R] épouse [K] et M. [P] [K] les sommes de 8 806 euros à titre de dommages et intérêts et de 4 000 euros sur le fondement de l’article 700 du code de procédure civile”. The facts mirror what can happen to a British seller: the buyers had sold, paid €16,012 of capital-gains tax, then rebuilt a main residence within two years and sought their money back, but the exemption wording was missing from the deed and the refund was refused. The appeal court reversed the first judges and made the office pay. The precedent matters for you in two ways. Instruct the notaire in writing, before completion, on the exemption, the holding computation and the representative’s details, and keep that letter. And if an omission has already cost you money, a liability claim against the office, which carries compulsory professional insurance, can recover what the tax appeal cannot. The same logic reaches the représentant fiscal: an accredited representative who miscalculates the allowances or misses a dispensation answers for its fault, and its contract usually provides for direct payment of any shortfall it causes.

Two cautions close this section. First, never let completion pressure make you sign a 2048-IMM you have not read. The form is in French, the figures bind you, and the notaire‘s accelerated timetable at the signing meeting is the worst moment to discover an error. Ask for the draft computation a week in advance, check the acquisition price, the works, the dates, the allowance percentages and the surtax band, and have the representative confirm each line in English in writing. Second, coordinate the French challenge with the British return. A French repayment obtained after you filed the British return changes the foreign-tax credit and may require amending the Self Assessment; a British enquiry into the credit does not suspend the French time limits. Run both calendars together from completion day, keep every document for at least six years, and treat the sale as a two-country file from the start rather than a French file with a British footnote.

Conclusion

Selling a French second home from Britain is a transaction France controls from start to finish: the treaty gives France the first taxing right, the notaire collects the 19% levy, the 17.2% social charges and the 2% to 6% surtax before you see the funds, and since Brexit an accredited représentant fiscal must stand behind the declaration. None of that makes the bill arbitrary. The holding allowances erase the income-tax slice after 22 years and the social-charges slice after 30, the CSG and CRDS exemption survives for British affiliates with only the 7.5% solidarity levy remaining, and the exemptions for former main homes protect recent leavers. Price the allowances into your timetable, appoint the representative when the compromis is signed, get the draft 2048-IMM in advance, claim the British foreign-tax credit on the same gain, and challenge promptly and in writing anything that departs from the official rules. Handled in that order, a sale that begins as a shock on completion day ends as a computation you can verify, defend and, where the years are on your side, reduce to very little.