You have retired to France, your UK State Pension is paid each week or each month by the Department for Work and Pensions, and a simple question keeps nagging you: where is that pension actually taxed now that the United Kingdom has left the European Union? Do you still pay tax in Britain, do you pay it in France, could both countries tax the same money, and why does a French social charge appear on a pension that was never earned in France? This article answers those questions in one place, for a British reader living in France, and every French term is explained the first time it is used. The short answer is reassuring on the main point and demanding on the details. Since Brexit changed nothing in the France-United Kingdom double tax treaty, your UK State Pension as a French resident is taxable only in France, it must be declared on your French tax return even when no British tax is taken, and it qualifies for the same 10 per cent deduction as a French pension. The difficulties that cost real money are the three classic traps: British tax still deducted at source because no treaty claim was filed, the French social charges known as CSG and CRDS applied at the full rate when an exemption certificate was available, and a government-service pension confused with a State Pension so that the wrong country taxes it. Each of these can be challenged, in France through a formal tax complaint and then the administrative courts, and in Britain through a treaty claim to HM Revenue and Customs, provided you act within the deadlines and keep the right paperwork. Paris and Ile-de-France readers will find local procedure notes throughout, because that is where most challenges are filed.
I. Your UK State Pension as a French resident is taxable only in France, and Britain must step aside
A. The France-United Kingdom treaty gives France the exclusive right to tax your State Pension
The rule that decides everything is Article 18 of the France-United Kingdom double tax treaty of 19 June 2008, published by decree and still fully in force after Brexit, because Brexit ended European Union membership, not bilateral tax treaties. Its rule is short and decisive: pensions and similar payments for past employment, paid to a person who lives in one of the two countries, are taxable only in that country of residence, subject only to the government-service exception examined below. A British retiree who is tax resident in France therefore owes income tax on the UK State Pension to France alone, and the United Kingdom has no treaty right to tax it. The French tax administration confirms the mechanism in its official doctrine: the Bulletin officiel des finances publiques on the Franco-British treaty sets out how residents of France claim treaty benefits on British-source pensions, and the English-language pages of the tax authority explain that foreign-source pensions must be declared in France, with double taxation eliminated by a tax credit where the treaty so provides. For a State Pension that is taxable only in France, there is no British tax to credit, because there should be no British tax at all, and the French return simply taxes the pension under domestic rules. That is why the Department for Work and Pensions pays the pension gross, without deducting British tax, once your position is regularised, and why any British deduction still appearing on a private pension slip next to it usually signals a missing treaty claim rather than a treaty problem. Practitioners who advise British clients in France describe exactly this picture: under the treaty most UK pension income received by French residents is taxed in France and not in the United Kingdom, the State Pension arrives gross, and the payer needs proof of French residence before it stops deducting tax at source. The practical instrument is the form called France-Individual, filed first with your local French tax office, the Service des impôts des particuliers, and then sent to HM Revenue and Customs, which instructs the payer to apply the treaty. Keep a copy of everything, because if the French administration later asks why no British tax was paid, that stamped form is your evidence that the exemption was treaty-based and not an omission.
Two misunderstandings need clearing up before going further, because they generate most of the double-tax bills this article helps you challenge. First, the State Pension is not a government-service pension. Government-service pensions, paid for work done for the British state itself, obey a different article, and confusing the two is the single most expensive classification error a British retiree in France can make. Your State Pension, built up through National Insurance contributions in ordinary employment or self-employment, falls under Article 18 and is taxed in France. A civil service, military, police or local-authority pension for actual government service falls under the rule examined in the next section. Second, Brexit did not move the State Pension into some new category. The treaty was signed in 2008, it allocates taxing rights bilaterally, and the United Kingdom leaving the European Union did not rewrite a single one of its articles. What Brexit changed is around the pension, not inside it: residence permits, healthcare affiliation through the S1 certificate, exchange of information, and the administrative friction of getting forms stamped on both sides of the Channel. The taxing rule itself survived intact, which is good news, because it means the considerable case law and doctrine built up under the treaty still protects you, and a French tax officer cannot invoke Brexit to tax something the treaty reserves to Britain, nor can HM Revenue and Customs invoke it to keep taxing something the treaty reserves to France.
B. French tax residence and the government-service exception decide which article applies to you
Article 18 protects you only if you are genuinely resident in France for tax purposes, so the residence test comes first and it is stricter than many newcomers expect. Article 4 B of the French General Tax Code, the Code général des impôts, treats you as domiciled in France if your home, your foyer, or your principal place of stay is in France, providing that “Les personnes qui ont en France leur foyer ou le lieu de leur séjour principal” are concerned, or if you carry on a professional activity in France unless it is merely ancillary, since “Celles qui exercent en France une activité professionnelle, salariée ou non, à moins qu’elles ne justifient que cette activité y est exercée à titre accessoire” are also covered, or if the centre of your economic interests is in France. In practice the administration looks at where your family home is, where you spend most nights, where your bank accounts and daily life are anchored, and it does not accept that a person living eleven months a year in the Dordogne or in Paris remains British-resident for tax simply because a house is kept in Kent. The 183-day threshold that everyone quotes is only one indicator among others, and keeping count of days without moving the centre of your life does not defeat the foyer test. If both countries claim you, the treaty contains a tie-breaker that looks in order at your permanent home, your centre of vital interests, your habitual residence and your nationality, and as a last resort the two administrations settle the case by mutual agreement, since the treaty provides that the competent authorities shall endeavour to resolve difficulties of interpretation or application by agreement. For a retired couple settled in France with a French home, French healthcare registration and French daily life, the answer is normally France, and the State Pension is then taxable only in France from the year residence starts, with arrival-year split rules applied carefully so that pre-departure British income is not swept into the French return.
The exception you must master is paragraph 2 of Article 19 of the same treaty, which governs pensions paid for government service and reverses the rule. In substance, a pension paid by one of the two States, or by its local authorities, for service rendered to that State is taxable only in the paying State, unless the recipient both lives in the other State and holds that other State’s nationality without also holding the paying State’s nationality, in which narrow case the residence State takes it. Applied plainly, a British civil service or armed forces pension paid for service to the British state is taxable only in Britain, unless you are both resident in France and French-national without also being British, in which narrow case France takes it. The companion doctrine confirms that such income, though exempt in France, must still be declared there so that it counts for the effective rate, the taux effectif, applied to your other French-taxable income, and France then grants a credit equal to the French tax on it, so the exemption does not become a rate advantage on the rest of the return. The trap for British retirees is the mixed career: twenty years in the National Health Service paid through an ordinary hospital payroll is generally not government service, while a pension paid directly by a ministry or a local authority for service as an official may be, and HM Revenue and Customs publishes a list of which schemes count. If you receive both a State Pension and a former-employer pension, split them from the start, because the State Pension goes to France under Article 18 while a true government-service pension stays in Britain under Article 19, and declaring the whole lot in one box guarantees either double taxation or a reassessment. When in doubt, ask for a written position from each administration rather than guessing, because a wrong guess corrected three years later carries interest and penalties that a timely question would have avoided.
II. France taxes the pension like its own, adds social charges, and every element can be challenged
A. Declare the gross pension on the French return and pay French tax at French rates
Once residence points to France, domestic French law takes over, and it treats your British State Pension exactly as it treats a French retirement pension. Article 79 of the General Tax Code provides that “Les traitements, indemnités, émoluments, salaires, pensions et rentes viagères concourent à la formation du revenu global servant de base à l’impôt sur le revenu”, which means pensions join your total worldwide income to form the single net amount on which progressive income tax is computed. You declare the gross annual amount actually paid by the Department for Work and Pensions, converted into euros at the rate applied on the date of each payment or, as most advisers accept in practice, at a consistent annual average rate disclosed on the return, and you declare it even if Britain deducted nothing, because exemption in Britain is never an exemption from declaration in France. The tax authority’s English guidance is explicit: income received abroad that is taxable in France must be declared by every member of the household, and where the treaty makes the income taxable in France, double taxation is removed by a credit, with the instruction to fill out returns nos. 2042, 2042 C and 2047. In concrete terms you enter the pension on the foreign-income return 2047, sections for pensions, and carry the total to the main return 2042, so that the calculation engine applies the treaty correctly. Since 2019 French pensions have been subject to withholding at source, the prélèvement à la source, and foreign pensions declared through the same system generate monthly or quarterly instalments, the acomptes contemporains, computed from your last return, which means a first full year in France often ends with a balancing payment in the autumn followed by smoother instalments the next year. Do not confuse those instalments with British PAYE: they are advance French tax, adjustable online when your income falls, and any British tax wrongly deducted is not an instalment but an error to reclaim from HM Revenue and Customs with the France-Individual procedure, not a credit to set against the French bill, because France grants a credit only for foreign tax levied in accordance with the treaty, and Article 18 leaves Britain nothing to levy on a State Pension.
The calculation itself holds one genuine advantage that softens the bill: the 10 per cent deduction for pensions. Article 158, paragraph 5-a of the General Tax Code sends pension income to the salary rules when it states that “Les revenus provenant de traitements publics et privés, indemnités, émoluments, salaires et pensions ainsi que de rentes viagères autres que celles mentionnées au 6 sont déterminés conformément aux dispositions des articles 79 à 90”, and then grants that “Les pensions et retraites font l’objet d’un abattement de 10 % qui ne peut excéder 4 439 €. Ce plafond s’applique au montant total des pensions et retraites perçues par l’ensemble des membres du foyer fiscal.” The passage continues with the floor and the indexation rule: “L’abattement indiqué au deuxième alinéa ne peut être inférieur à 454 €, sans pouvoir excéder le montant brut des pensions et retraites”, with both figures revised each year in line with the top of the first income-tax band, so you must check the current year’s thresholds on the return itself rather than memorising the numbers quoted here. Your British State Pension therefore enters the French progressive scale, the barème, alongside any French or other worldwide income, after the 10 per cent deduction, and the household system, the quotient familial, divides that net income into parts, parts fiscales, one for a single person and two for a married couple, which usually flatters a single-pension household. Two further points complete the picture. First, if you also receive a British government-service pension that is exempt in France, it is still entered on the return so that the taux effectif, the effective-rate rule, can lift the rate applied to your taxable income, and the treaty then neutralises the exempt slice through its credit rule, since the elimination-of-double-taxation article gives the French resident a credit against French tax, equal, for income of this kind, to the French tax attributable to that income, provided the resident was subject to United Kingdom tax on it under the treaty. Second, the year you arrive or leave demands split-year care: income received while still British-resident belongs to Britain, income received once French-resident belongs to France, and the departure paperwork, the P85 notice to HM Revenue and Customs and the French arrival return, should use the same residence date, because mismatched dates are the commonest cause of both countries taxing the same spring quarter. Readers in Paris file with the Service des impôts des particuliers of their arrondissement and manage everything, returns, instalment rates, claims, through the impots.gouv.fr personal account, which is also the channel for the formal complaint described below, and keeping that account’s messaging history is already half of your evidence file.
B. Social charges are the real surcharge, and affiliation plus paperwork decide whether you pay them
Income tax is only half the French bill, because France adds social charges, the prélèvements sociaux, and on pensions they are heavy. The headline rate to memorise is 9.1 per cent on retirement pensions for a person affiliated to the French health system, made of the CSG, contribution sociale généralisée, plus the CRDS, contribution au remboursement de la dette sociale, plus the CASA solidarity levy, and the CSG slice itself is fixed by statute since Article L136-8 of the Social Security Code states that “Sont assujetties à la contribution au taux de 8,3 % les pensions de retraite, et les pensions d’invalidité.” Reduced CSG rates exist for modest incomes, and total exemption exists below a threshold of taxable income, the revenu fiscal de référence, so a small State Pension as sole income may attract little or no charge, but a comfortable household pays the full rate, and the charge is computed on the gross pension with no 10 per cent deduction. The decisive question is therefore not the rate but the liability itself: are you, as a British pensioner in France, within the French social security system at all? If you hold a British S1 healthcare certificate, registered with your local Caisse primaire d’assurance maladie, your healthcare costs are borne by Britain and you are not affiliated to the French system for health purposes, so the CSG and CRDS on your British pension fall away, and only the 7.5 per cent solidarity levy on income, the prelevement de solidarite, remains on the pension, which is precisely the 9.1 per cent trap that advisers warn against: pensioners who could have claimed the S1 route but never registered pay the full charge every year until they fix it. Since Brexit the S1 route remains open under the post-Brexit social security coordination for British State Pensioners moving to France, and the certificate is requested from the UK side before registration in France, so a retiree planning the move should apply early and keep the dated certificate, because the exemption runs from affiliation facts, not from the day you first hear about it.
When the administration gets affiliation wrong, the courts have drawn the map, and two decisions you can cite by number carry the argument. The leading authority is Conseil d’Etat, 24 July 2019, No. 416662, where the court records that “Il ressort des pièces du dossier soumis aux juges du fond que MmeB…, qui réside fiscalement en France, a été assujettie au titre des années 2011, 2012 et 2013 à la contribution sociale généralisée (CSG) et à la contribution au remboursement de la dette sociale (CRDS) à raison des pensions de droit suisse qu’elle perçoit en tant qu’ayant-droit de son conjoint décédé.” The ruling then works through the European coordination regulations to decide whether France, as the state of residence, was entitled to levy CSG and CRDS on a foreign pension, holding that inclusion of the foreign pension in the base is possible where French social legislation applies to the person, but only within the contribution attributable to the French pension and subject to proof that the person is not placed worse off than someone who worked entirely in France. The complementary authority is Administrative Court of Appeal of Nancy, 14 May 2019, No. 18NC03448, which quotes the coordination rule in full: “L’institution d’un État membre qui applique une législation prévoyant des retenues de cotisations pour la couverture des prestations de maladie, de maternité et de paternité assimilées, ne peut procéder à l’appel et au recouvrement de ces cotisations, calculées selon la législation qu’elle applique, que dans la mesure où les dépenses liées aux prestations servies en vertu des articles 23 à 26 sont à la charge d’une institution dudit État membre”, and draws the evidential consequence that a pensioner contesting the levies must prove not only affiliation to the residence state’s scheme but that benefits are received under that state’s legislation and not for the account of the French funds, since an S1 registration points the other way. Read together for a British S1 holder in France, these cases say: produce the S1, prove the British institution bears the healthcare cost, and the French CSG/CRDS on the British pension has no base, while a pensioner genuinely under the French health system, under the PUMA universal cover after stable residence, pays the charges like any French pensioner. The official service-public pages on CSG and CRDS on replacement income give the current thresholds and rates to check each year, and the GOV.UK guidance on tax when you retire abroad states the British side of the position, so a challenge file that joins the S1, the CPAM registration, the DWP gross-payment letters and these two court numbers is already structured the way the judge will read it.
The same single-legislation logic appears in the Court of Cassation for pensioners who resume work across a border, a situation many semi-retired Britons in France will recognise. In Cour de cassation, Second Civil Chamber, 9 May 2018, No. 17-16.341, a French pensioner living in France who resumed salaried work in Switzerland was held to fall under the Swiss health insurance scheme, the court recalling that “il résulte de l’article 34 du règlement (CEE) n° 1408/71 susmentionné que, pour l’application du chapitre 1er du titre III dudit règlement relatif aux prestations de maladie et maternité, le titulaire d’une pension ou d’une rente qui a droit aux prestations prévues par la législation d’un Etat membre au titre d’une activité professionnelle est considéré comme un travailleur salarié ou non salarié”, and approving the appeal court for holding that “le règlement susmentionné pose le principe d’unicité de la législation applicable et fait prévaloir celle de l’Etat où est exercée l’activité” so that “au cours de l’année 2009 Mme X…, qui résidait en France et exerçait une activité salariée en Suisse, relevait du régime d’assurance maladie suisse, peu important qu’elle bénéficiât d’une pension de retraite en France”. The decision predates Brexit and applies the former Community regulation, now replaced for British cases by the post-Brexit social security coordination protocol, but the lesson survives: where you work decides which health system covers you, and that affiliation answer drives the CSG analysis on the pension.
Challenging a wrong bill follows a fixed ladder, and each rung has its own deadline, so start at once and never let a notice sit. First, file a réclamation, a formal complaint, from your impots.gouv.fr account or by recorded letter to your Service des impôts des particuliers, identifying the assessment, the tax or charge contested, the treaty article or affiliation proof relied on, and the precise amount claimed, and attach the S1, the France-Individual acknowledgement, the DWP statements and the conversion computation. The administration must answer with a reasoned decision, and silence kept beyond the statutory period opens the court door. Second, if the answer is negative or never comes, appeal to the administrative tribunal of your residence: in Ile-de-France that is the Tribunal administratif de Paris for the capital, and the tribunals of Montreuil, Versailles, Cergy-Pontoise or Melun for the surrounding departments, each judging the same treaty and affiliation arguments with full access to the coordination case law above. Third, on the British side, pursue the parallel track with HM Revenue and Customs for any tax deducted in breach of Article 18, using the France-Individual claim and, if refused, the review and tribunal procedure, because a British deduction left standing while France taxes the same pension is exactly the double taxation the treaty exists to kill, and the treaty’s mutual-agreement clause lets the two administrations settle between themselves when a case genuinely straddles the line. Throughout, keep the classification clean: State Pension to France under Article 18 with gross payment and French declaration, government-service pension to Britain under Article 19 with French declaration for the effective rate and a matching credit, S1 holders outside CSG/CRDS with proof of British-borne healthcare, PUMA affiliates inside it like their French neighbours. Done in that order, with documents dated and kept, most cases end at the complaint stage, and those that go further reach the judge with the treaty text, the two court numbers and the affiliation file already aligned.
Conclusion
A British State Pension in France after Brexit is taxed in one country only, and that country is France: Article 18 of the 2008 treaty says so, the French return taxes the gross pension with the same 10 per cent deduction as domestic pensions, and Britain’s only lawful role is to pay gross once the France-Individual claim is in place. The two bills that still hurt, British withholding left running and French social charges levied at the 8.3 per cent statutory rate on an S1 holder, are both administrative errors with documented remedies, and the Conseil d’Etat, Nancy and Court of Cassation decisions above give those remedies their legal backbone. Declare everything, classify each pension under its own article, register the S1 before the charges accrue, and challenge quickly and in writing whenever an assessment departs from that scheme. The system rewards the organised filer and penalises the silent one, and on a pension paid for decades the difference between those two postures is worth many times the effort of one careful return.