You own a flat in Paris, Nice or the Alps, you live in London, Manchester or Edinburgh, and between your own stays the property sits empty. Listing it for short-term guests looks like the obvious answer. After Brexit, the letting itself works exactly as it does for any non-resident owner, but every control around it has tightened: a national registration number is now compulsory before you advertise, Paris and many other cities require a prior change-of-use permission that a second-home owner will rarely obtain for a whole flat, platforms must display your number and share your rental data with the town hall, the tax thresholds for furnished tourist lets have been cut sharply, and the civil fine for an unlawful change of use can reach 100,000 euros per property. This guide explains, for a British second-home owner, which registration to complete, when a change-of-use permission is needed and why Paris is a special case, how the French tax return treats your short-term rents whether you remain UK resident or have become French resident, and how to challenge a fine, a return-to-housing order or a tax reassessment. French terms are explained at first use. The position is stated as at 21 October 2026 for the rules described, and individual town-hall regulations should always be checked for your postcode.

I. Can a British second-home owner lawfully list a French flat for short-term guests, and which permission comes first?

Short answer: yes, provided the two preliminary controls are cleared in the right order. Registration comes first everywhere in France, and in Paris, Lyon, Bordeaux and the other municipalities that have introduced the prior-permission system, a change-of-use permission comes second. The two steps answer different questions. Registration tells the town hall who you are and where the flat is. The permission tells the town hall that housing may lawfully be turned into tourist accommodation. A British passport changes nothing in either step: the rules apply to the property, not to your nationality. What Brexit does change is your residence position, which matters for tax and for how many nights you may let, as explained below.

A. Do I need to register my furnished tourist flat and display the number on the listing?

A meublé de tourisme, meaning a furnished tourist flat or house, is defined by French tourism law as villas, flats or studios, for the exclusive use of the tenant, offered for rent to passing guests who do not live there and whose stay takes the form of a daily, weekly or monthly letting. The statutory definition states that:

“les meublés de tourisme sont des villas, appartements ou studios meublés, à l’usage exclusif du locataire, offerts à la location à une clientèle de passage qui n’y élit pas domicile et qui y effectue un séjour caractérisé par une location à la journée, à la semaine ou au mois” (Article L324-1-1 of the Tourism Code).

If your flat matches that description when you are not there, which a typical holiday let does, you are a loueur de meublé de tourisme, a furnished tourist-let host, and registration is compulsory before the first advertisement goes online. The same article provides that:

“Toute personne qui offre à la location un meublé de tourisme procède préalablement en personne à une déclaration soumise à enregistrement auprès d’un téléservice national opéré par l’organisme public unique mentionné au premier alinéa du II de l’article L. 324-2-1” (Article L324-1-1 of the Tourism Code).

In practice, you file the declaration yourself on the national teleservice, you prove whether the flat is your main home (résidence principale) or not, and the system immediately returns an electronic acknowledgement containing a declaration number. That number, with the supporting information and documents, is passed without delay to the municipality where the flat is located. You must update the declaration whenever the information changes and renew it when it expires. A decree lists the documents required, including a French income-tax notice in the host’s name showing the address of the let property as the place of taxation, which is precisely the document a British second-home owner must plan for: if you have never filed a French return for the property, expect the registration desk to ask how the address appears on your French tax record.

The declaration number must then appear in every advertisement for the flat. The platform rule is direct. The intermediary, which means any person or digital platform that helps market the let, must inform you of the declaration and permission duties, obtain from you before publication a sworn statement that those duties have been met, together with the declaration number, and publish that number in each listing. The Code states that:

“Elle publie, dans toute annonce relative à ce meublé, ce numéro de déclaration.” (Article L324-2-1 of the Tourism Code).

For a British owner this has three practical consequences. First, an advertisement without a number is itself an offence, even if the underlying letting would have been lawful: the declaration fines reach 10,000 euros for a missing declaration and 20,000 euros for a false declaration or a false number. Second, the platform now feeds your activity data to the municipality through the single public body, so the town hall no longer needs to find your listing by chance; it receives aggregated and, on request, individualised letting data, and it is automatically told when a flat declared as a main home has been let beyond the legal ceiling in a calendar year. Third, the mayor can suspend a declaration number and order platforms to delist the advertisement where the premises are subject to a safety or insalubrity order. Before Brexit many British owners treated registration as optional paperwork in cities that had not yet set up a register. That era is over: the national teleservice, the mandatory number in every advertisement, and the automatic data feed make the declaration the gateway to every lawful short-term let.

Paris and Île-de-France add a local layer worth understanding early. Paris requires every furnished tourist let, main home or second home, to hold a declaration number, and its enforcement unit cross-checks platform data systematically. If your Paris flat is your second home, the declaration will record it as such, and that classification directs the town hall to the second question, the change-of-use permission, which is where most second-home projects in Paris succeed or fail. Outside Paris, many municipalities in the inner suburbs apply the same logic, while smaller towns may still only require the declaration. Check the municipal order for your arrondissement or commune before spending money on furniture or photography: the declaration is quick, but it never replaces the permission described next.

B. Do I need change-of-use permission in Paris and other controlled cities, and what is the 120-day second-home limit?

The changement d’usage, or change of use, is the most misunderstood concept in French short-term letting. It has nothing to do with planning permission for building works. It is a housing-protection permission: in designated municipalities, turning residential premises into tourist accommodation needs the prior agreement of the town hall, because each conversion removes a home from the local housing stock. The decisive rule now reads:

The Code then states the decisive rule: letting residential premises as a furnished tourist let within the meaning of Article L324-1-1 of the Tourism Code itself counts as a change of use (Article L631-7 of the Construction and Housing Code).

In other words, repeated short-term letting of a residential flat to passing guests is itself the change of use. The Cour de cassation, France’s highest civil court, has confirmed the logic in plain terms:

“Le fait de louer un local meublé destiné à l’habitation de manière répétée pour de courtes durées à une clientèle de passage qui n’y élit pas domicile constitue un changement d’usage au sens de ce texte.” (Cour de cassation, Third Civil Chamber, 27 June 2024, appeal no. 23-13.131).

The same judgment settled a defence that many owners used to raise: a tourism classification (classement en meublé de tourisme), the star-rating visit organised through the tourist office, does not replace the town hall’s permission. The Court held that:

“une décision de classement en meublé de tourisme ne peut se substituer à l’autorisation de changement d’usage prévue à l’article L. 631-7 du code de la construction et de l’habitation” (Cour de cassation, Third Civil Chamber, 27 June 2024, appeal no. 23-13.131).

So the star plaque on the door proves comfort, not legality. Only the municipal permission proves legality in a controlled city.

Whether your flat even counts as residential premises, a local à usage d’habitation, follows precise statutory presumptions rewritten by the Act of 19 November 2024, known as the Le Meur Act, which strengthened local regulation of tourist lets. Since that reform, the Code provides that:

“un local est réputé à usage d’habitation s’il était affecté à cet usage soit à une date comprise entre le 1er janvier 1970 et le 31 décembre 1976 inclus, soit à n’importe quel moment au cours des trente dernières années précédant la demande d’autorisation préalable au changement d’usage ou la contestation de l’usage” (Article L631-7 of the Construction and Housing Code).

Use may be proved by any means, and the burden lies on the party alleging unlawful use, while premises built or converted after 1 January 1970 are presumed to have the use for which the works were authorised. For pending cases about lets that predate the reform, the Cour de cassation issued an advisory opinion on 10 April 2025 holding that the old criteria continue to govern: in the Court’s summary, where a civil fine is sought for a change of use that occurred before the new Act took effect, the residential character is assessed under the former law (Cour de cassation, advisory opinion of 10 April 2025, no. 25-70.002). The old formula, quoted in the opinion, was that:

“Pour l’application de la présente section, un local est réputé à usage d’habitation s’il était affecté à cet usage au 1er janvier 1970. Cette affectation peut être établie par tout mode de preuve.” (Cour de cassation, advisory opinion of 10 April 2025, no. 25-70.002).

The earlier Paris litigation that tested the whole system against European Union free-movement law also belongs in the picture. In the Cali Apartments cases, owners argued that the Paris permission system breached the freedom to provide services. The Third Civil Chamber stayed proceedings in November 2018 and referred the question to the Court of Justice of the European Union (Cour de cassation, Third Civil Chamber, 15 November 2018, appeal no. 17-26.156, order for reference). The European Court then upheld a permission system justified by the fight against a shortage of long-term rental housing, and the French courts have applied the system ever since. British owners sometimes ask whether Brexit reopens that European argument. It does not: the United Kingdom is now a third country, and the permission system is French domestic housing law applied to the property regardless of the owner’s nationality.

The 120-day rule needs careful handling because it helps a different owner from you. Where a flat is the host’s main home, the law caps short-term letting of that main home, and platforms must stop offering a main home once they know the ceiling has been exceeded. A British second-home owner whose main home is in the United Kingdom cannot use that ceiling as a right to let for 120 days. Your flat is by definition not your French main home, so in a city with the permission system the town hall will ask for the permission, not for a day count. In Paris, that permission for a whole second home converted to full-time tourist letting is in practice granted only with compensation, meaning you must fund the conversion of an equivalent non-residential space back into housing, a costly mechanism designed for professionals. The realistic lawful routes for a British second-home owner in Paris are therefore narrow: a long-term furnished tenancy of nine months or more to a student or mobile worker, which is not a tourist let, or a carefully authorised arrangement, but not an all-year short-term listing of the entire flat without permission. Outside the controlled zone, the permission is not required and the declaration plus tax compliance may be enough, which is why the postcode matters more than the nationality. For the longer letting alternative and its tax treatment, see our companion guide on letting a French property as a British owner (British landlord guide to letting French property, tax and registration).

II. What tax and penalties does a British host face in France, and how do I challenge them?

Once the flat is listed, two separate risk areas begin: the French tax on the rents, and the penalties if the town hall or the tax office considers the letting unlawful or under-declared. British hosts often assume that paying tax in the United Kingdom on worldwide income settles the French side. Under the France–United Kingdom double tax treaty, income from immovable property is taxable in the country where the property stands, so France taxes the French rents first and the United Kingdom then gives relief. French registration, French tax returns and French social charges therefore cannot be avoided by reporting everything to HM Revenue and Customs alone.

A. How is my short-term rental income taxed in France as a British resident or non-resident?

Furnished letting in France is a commercial activity for income-tax purposes, even when the owner is a private individual. The General Tax Code provides that:

“Personnes qui donnent en location directe ou indirecte des locaux d’habitation meublés” (Article 35 of the General Tax Code)

earn industrial and commercial profits (bénéfices industriels et commerciaux, known as BIC). That single classification drives everything: you must file a French professional or BIC return for the rents, you may deduct actual costs or claim a flat-rate allowance under the micro-BIC scheme if your turnover is below the ceiling, and the social-contribution treatment follows the BIC analysis.

The Le Meur Act cut the micro-BIC ceilings for tourist lets sharply, and the current thresholds are the ones to use for 2026 income. The Code now provides a dedicated low ceiling for tourist lets:

“1° bis 15 000 € s’il s’agit d’entreprises dont l’activité principale est de louer directement ou indirectement des meublés de tourisme, au sens du I de l’article L. 324-1-1 du code du tourisme, autres que ceux mentionnés aux 1° et 2° du I de l’article 1414 bis du présent code” (Article 50-0 of the General Tax Code).

Below that ceiling the taxable profit is turnover minus a flat allowance, and the allowance for tourist lets is now modest:

“d’un abattement de 30 % pour le chiffre d’affaires provenant d’activités de la catégorie mentionnée au 1° bis” (Article 50-0 of the General Tax Code).

The allowance cannot be less than 305 euros. Above the ceiling, or by election, the host is under the real-profit scheme (régime réel), deducting depreciation, agency fees, insurance, co-ownership charges attributable to the letting, interest and the tourist-tax collection costs. Classified tourist lets in low-density areas keep higher ceilings and allowances under the exemptions cross-referred to in the article, which is why the classification visit can still matter for tax even though it never replaces the town hall’s change-of-use permission. A British owner who expected the old 77,700-euro ceiling and 50 per cent allowance should recalculate: at 20,000 euros of gross short-term rents, the old allowance sheltered 10,000 euros while the new 30 per cent allowance shelters only 6,000 euros, and above 15,000 euros the micro scheme is no longer available at all for an unclassified city-centre tourist let.

Residence then decides the rest of the return. If you remain UK resident and French tax resident nowhere, you file a French non-resident return reporting the French-source BIC, you pay French income tax on that profit at the minimum developling rate applicable to non-residents, and you remain liable to the prélèvements sociaux, the French social levies on capital and rental income, at 17.2 per cent, because the exemption for holders of a European health-insurance affiliation does not extend to a purely British affiliation since Brexit unless a valid S1 healthcare certificate shifts the position. If you have become French resident, you report the worldwide income in France, claim the treaty foreign-tax credit for any United Kingdom tax on the same rents, and the social levies and contribution sociale généralisée apply under the ordinary resident rules. In both cases the visitor tax (taxe de séjour), set by the municipality and collected from the guest, must be remitted; platforms collect it automatically in many cities, but the host remains responsible where they do not. Keep every platform payout statement, the declaration number acknowledgement, the tourist-tax receipts, and the day-count record the municipality may demand up to 31 December of the following year: the town hall can require you to report the number of days the flat was let, whether or not it is your main home, and you must reply within one month giving the address and the declaration number.

Two British-specific pitfalls deserve emphasis. First, mortgage interest on a UK loan used to buy the French flat is deductible under the real-profit scheme only with clear tracing between the borrowing and the let property, translated loan statements, and proof of payment; a bare assertion that the London remortgage funded the Paris purchase will not survive an audit. Second, capital-gains treatment on a later sale is separate from the rental regime: short-term letting does not by itself change the private-residence exemption, which for a second home is unavailable in any event, but sustained letting with services can push borderline activity towards a professional classification with different social-charge consequences. Take advice on the chosen scheme before the first tax year closes, because moving from micro-BIC to the real-profit scheme, or back, follows strict option deadlines.

B. How do I challenge a 100,000-euro fine, a return-to-housing order or a tax bill?

The sanction for an unlawful change of use is a civil fine, not a criminal conviction, but its scale shocks British owners used to fixed-penalty logic. The Code provides that:

“Toute personne qui enfreint les dispositions des articles L. 631-7 ou L. 631-7-1 A ou qui ne se conforme pas aux conditions ou obligations imposées en application des mêmes articles L. 631-7 et L. 631-7-1 A est condamnée à une amende civile dont le montant ne peut excéder 100 000 € par local irrégulièrement transformé.” (Article L651-2 of the Construction and Housing Code).

The fine is ordered by the president of the judicial court (tribunal judiciaire) ruling under the accelerated procedure on application by the municipality, and its proceeds go to the municipality. The same judge may order the return of the premises to residential use within a fixed period, failing which a periodic penalty of up to 1,000 euros per day per square metre may accrue, with the administration empowered to carry out the eviction and works at the offender’s expense once the deadline passes. Alongside that headline fine sit the declaration fines described earlier, up to 10,000 euros for a missing declaration, 20,000 euros for a false one, 50,000 euros for obstructing the mayor’s suspension order, and 15,000 euros for exceeding the main-home ceiling, most of them pronounced by the same accelerated procedure at the municipality’s request.

A British defendant is not without defences, but they must be raised in the French way with French evidence. First, contest the residential character of the premises under the correct temporal law: for lets that predate the Le Meur Act, rely on the advisory opinion holding that the former 1970 test applies (Cour de cassation, advisory opinion of 10 April 2025, no. 25-70.002); for later lets, work through the new 1970–1976 or thirty-year window with title deeds, historic housing-tax records, old leases and planning authorisations. The burden of proving unlawful use lies on the party alleging it, so an incomplete municipal file can be challenged. Second, contest the facts of the letting: isolated stays by friends, a genuine nine-month student tenancy, or a caretaker’s occupation are not repeated short-term letting to passing guests, and the municipality must prove the pattern, increasingly through platform data whose completeness and attribution can be tested. Third, check standing and procedure: only the municipality of the property, the housing authority, the competent planning body or the national housing agency may apply, before the court of the property’s location, and limitation and notification defects are litigated points. Fourth, argue proportionality of the amount: judges graduate the fine by gravity, duration, rental profit and repeat offending, and documented regularisation, such as immediate delisting, a filed declaration and a switch to long-term letting, supports a lower figure even where liability is established.

Tax reassessments follow a different track with strict time limits. The French tax office sends a reasoned correction proposal (proposition de rectification), and the taxpayer normally has thirty days to respond with observations and supporting documents before the assessment becomes final. A British non-resident who ignores the letter because it arrived at the French flat while they were in London loses the earliest and cheapest opportunity to narrow the dispute. Reply within the period, in French, addressing each adjustment: micro-BIC ceiling applied, allowance rate used, deductible charges rejected, social levies charged, and penalties for deliberate failure or concealed activity. Penalties range from 10 per cent for late declaration to 40 per cent for deliberate breach and 80 per cent for concealed activity, plus late-payment interest, and each uplift must be reasoned. If the assessment is maintained, the remedies run through a formal administrative claim (réclamation contentieuse) to the tax office, then appeal to the administrative court (tribunal administratif) within two months of the rejection decision. Throughout, the treaty position should be pleaded precisely: France taxes the rents first as immovable-property income, the United Kingdom relieves double taxation, and the French file should show the HMRC return position so that the same pound of rent is not taxed twice without relief. Where the dispute concerns the visitor tax or the declaration fines rather than income tax, the competent court is the judicial court, not the administrative court, and mixing up the two routes is the most common procedural error.

Practical evidence wins these cases. Keep the declaration acknowledgement and number, every advertisement screenshot showing the number, the sworn statement given to the platform, platform payout and occupancy reports, the day-count spreadsheet, the co-ownership rules and any general-meeting vote on short-term lets, correspondence with the town hall, the French tax returns and notices, the United Kingdom returns showing the same income, loan documentation with fund tracing, and a dated record of when the flat was occupied by you, your family or long-term tenants. A file that proves registration, honest tax filing and prompt regularisation will not always avoid liability, but it consistently reduces fines and penalties and shortens disputes. An empty file invites the maximum.

Conclusion

A British second-home owner can still let a French flat short-term after Brexit, but the lawful path is narrower and more documented than it once was. Register the tourist let on the national teleservice and display the number in every advertisement, obtain the town hall’s change-of-use permission wherever the local system requires it, understanding that a Paris second home will rarely secure that permission for all-year tourist letting, and file the French BIC return on the rents under the reduced micro-BIC ceilings or the real-profit scheme. Where a fine, a return-to-housing order or a tax reassessment arrives, challenge the residential classification under the correct temporal law, test the municipality’s proof of repeated short-term letting, graduate the penalty with evidence of regularisation, and meet the thirty-day and two-month reply limits on the tax side. With the declaration number, the permission position and the tax file in order before the first guest arrives, the letting becomes a manageable compliance exercise rather than a dispute.