For a British citizen living in France, a French assessment of social contributions on a UK State Pension can look contradictory: the pension is paid by the Department for Work and Pensions, healthcare is funded by the United Kingdom, and a portable S1 document has been registered with a French primary health-insurance fund (the caisse primaire d’assurance maladie, or CPAM). Yet the French tax authority may still ask for the contribution sociale généralisée (CSG, the general social contribution) and the contribution au remboursement de la dette sociale (CRDS, the social-debt repayment contribution) on the pension. The answer is not obtained by looking at the S1 in isolation.
The legal question is whether France may treat you as both tax-resident in France and financially covered by a compulsory French health-insurance scheme for the relevant period. An S1 can be powerful evidence that the United Kingdom remains responsible for healthcare costs, but its registration in France is not an automatic exemption certificate for every tax or social charge. The pension’s classification, the France–UK tax treaty, any French pension or employment, and the exact wording of the assessment must be checked together.
This guide sets out the test and the practical claim route. It also explains why the recent Conseil d’État decision no. 473997 must be read carefully: it concerns a Swiss pension and a French-resident pensioner who was subject to the French system. It does not turn every UK S1 holder into a French contributor, nor does it create a universal refund. It does, however, make a precise evidential file more important when a British pensioner asks the Direction générale des finances publiques (DGFiP, the French public-finance administration) to cancel or repay CSG and CRDS.
I. When can France charge CSG and CRDS on a UK State Pension?
A. Does an S1 make a British pensioner exempt from French social contributions?
The starting point is the French social-security test, not the name printed on the pension statement. Article L. 136-1 of the Social Security Code opens with the words: “Il est institué une contribution sociale sur les revenus d’activité et sur les revenus de remplacement”. It then identifies the relevant people as those who are both “considérées comme domiciliées en France” and “à la charge … d’un régime obligatoire français d’assurance maladie”. In English, the contribution attaches to people who are tax-domiciled in France and covered, in some capacity, by a compulsory French health-insurance scheme.
That is a double condition. The first limb is tax residence. The second is social-security responsibility. A person can receive French healthcare without the French state being the institution that ultimately bears the cost. That is the practical role of an S1: the document allows a person entitled to healthcare from one state to register for healthcare in the state of residence, while the competent state reimburses the cost under the applicable coordination arrangement. The French CPAM processes the registration and care, but that administrative contact does not by itself answer which state is legally competent.
For a British pensioner, the strongest potential challenge normally has a clear factual pattern: the United Kingdom issued a valid S1; the document covers the period for which contributions were assessed; the S1 was registered in France; the United Kingdom remained the competent state for healthcare; and the claimant was not otherwise brought into the French compulsory scheme by French employment, a French pension or another applicable status. That pattern does not guarantee success. It identifies the evidence needed to argue that the second limb of Article L. 136-1 was not met.
The United Kingdom’s official guidance on social-security arrangements describes the S1 route for people whose UK State Pension gives rise to reciprocal healthcare rights. The guidance explains that a UK pensioner within the relevant protected arrangements can have UK-funded healthcare in the country of residence. The applicable route may depend on the Withdrawal Agreement, the later UK–EU arrangements, the date of residence, previous periods of insurance and whether another state pays a pension. A person who moved to France after Brexit cannot simply rely on an older S1 letter from a different legal period.
Registration with a CPAM must therefore be separated from affiliation to the French scheme. Ask the CPAM for the registration decision and preserve the S1 reference, the date it was accepted and any letter stating which institution bears the healthcare cost. If the French administration has recorded the person as being covered by the French system while the UK institution has issued an S1 for the same period, the inconsistency should be identified in writing. If the S1 has expired, been replaced or never covered the disputed year, a challenge based only on a current Carte Vitale is weak.
French tax residence is analysed separately. Article 4 B of the General Tax Code includes the test of having in France “son foyer ou le lieu de son séjour principal”. It also refers to professional activity and the centre of economic interests, subject to the treaty tie-breaker. A British pensioner may be tax-resident in France while remaining attached to the UK for healthcare. That combination is legally possible, and it is precisely why a tax-residence certificate does not settle the social-security limb.
The reverse is also possible. A person may say “I have an S1” while the facts show French employment, French self-employment, a French pension that determines the competent legislation, or an elective French affiliation that is not replaced by the UK document. A French pension can be especially important in a multi-pension case. The assessment must be tested against the rules applicable to the period, not against a general statement that “the UK pays the larger pension” or that “the S1 is registered at the mairie”.
A useful first-page matrix should state, for each tax year:
- where the person lived and where the tax household was located;
- which institution issued the S1 and the precise dates covered;
- whether a French pension, salary, self-employed activity or unemployment benefit existed;
- which state was identified as competent for healthcare;
- which pension was declared in France and under which treaty article; and
- the document and line on which CSG, CRDS or the contribution additionnelle de solidarité pour l’autonomie (CASA, the additional solidarity contribution for autonomy) was assessed.
The S1 is therefore evidence, not a slogan. It can support a refund claim where it proves that the United Kingdom remained responsible for healthcare and France applied the wrong social-security classification. It cannot erase a French affiliation that the facts establish, and it cannot replace the analysis of the tax treaty or the pension’s legal nature.
B. How do tax residence, pension type and French healthcare affiliation change the calculation?
The second part of the analysis concerns the pension itself. “UK State Pension” should be used precisely. It is not automatically the same as a UK civil-service pension, an NHS pension, a local-government pension, a private workplace pension, a self-invested personal pension or a QROPS payment. The France–UK tax treaty may allocate taxing rights differently according to the source and public or private character of the pension. The French tax authority’s own guidance recommends checking whether the pension is private, a social-security pension or a public pension before applying the treaty.
The relevant treaty text should be read with the pension statement, not substituted by it. The official France–UK income-tax convention published by impots.gouv.fr is the reference document for the allocation of taxing rights. The British pension article already published on this site explains the declaration and treaty classification questions in greater detail; this article addresses the separate CSG and CRDS issue. A pension may be taxable in France without being subject to French social contributions if the social-security limb fails. Conversely, a pension that is not paid by France can still enter the French social-contribution base when the statutory conditions are met.
The official 2026 notice for form 2041-GG describes foreign-source replacement income as including retirement and invalidity pensions. It states that CSG and CRDS apply when the taxpayer is both domiciled in France under Article 4 B of the General Tax Code and “à la charge, à quelque titre que ce soit, d’un régime obligatoire français d’assurance maladie”. It also confirms that foreign-source pension contributions are generally collected by the DGFiP by assessment rather than being deducted by the UK pension provider. This explains why a British pensioner may receive a French tax notice even though the UK pays the pension and no UK statement shows a French deduction.
The rate is a separate question from liability. Article L. 136-8 of the Social Security Code currently states: “Sont assujetties à la contribution au taux de 8,3 % les pensions de retraite, et les pensions d’invalidité.” Lower rates or an exemption can apply by reference to the taxpayer’s revenu fiscal de référence (RFR, the reference taxable income) and household shares. The 2026 official table also identifies CSG at 3.8%, 6.6% or 8.3% for pensions, CRDS at 0.5%, and CASA at 0.3% in the cases stated. A low-income exemption is not the same legal argument as an S1-based exemption.
CASA must not be overlooked. Article L. 137-41 of the Social Security Code provides: “Est instituée une contribution additionnelle de solidarité pour l’autonomie au taux de 0,3 %”. The article links the charge to retirement and invalidity benefits and provides exclusions based on the statutory income thresholds. A claim should identify each line separately. Asking only for “the social contributions” can obscure a partial entitlement, a rate error or a CASA condition that is different from the CSG rate.
CRDS has its own legal basis. Article 14 of Ordinance no. 96-50 of 24 January 1996 refers to “une contribution sur les revenus d’activité et de remplacement” and links its base to the Social Security Code. The official tax notice treats CRDS as a 0.5% charge attached to the relevant foreign pension where the statutory conditions are satisfied. The notice, the pension amount and the legal basis should be compared; a line labelled “prélèvements sociaux” is not enough to determine whether the amount is CSG, CRDS, CASA, a health contribution or a charge on a different category of income.
For foreign pensions, the taxable and contribution base is normally the gross pension without the ordinary ten-percent income-tax allowance. The 2041-GG notice gives the reporting boxes for the applicable CSG rate, including 8TX for the reduced rate, 8TH for the median rate and 8TV for the normal rate, subject to the relevant year and the taxpayer’s situation. The French pension must also be declared for income tax under the correct treaty treatment. An error in the box can be challenged as a calculation error, but a box correction does not replace a formal claim if the tax notice has already been issued.
Do not import the property-income exemption into the pension analysis. The public impots.gouv.fr page explaining the UK exemption for people affiliated to a foreign social-security scheme concerns French-source property income and related capital gains. It is useful for a UK owner of a French second home, but it does not establish that a UK State Pension is automatically free of CSG and CRDS. The foreign pension notice and the BOFiP position on foreign pensions apply the double test of French tax domicile and French compulsory health affiliation. This distinction is a material safeguard against an attractive but wrong refund argument.
The recent case law reinforces the need for factual precision. In Conseil d’État, 25 October 2024, no. 473997, the court held, in a Swiss pension case, that the current coordination rules do not require the competent state to cap contributions at the amount of the pension it pays. The decision concerned a French-resident person with a French pension and a Swiss pension, not a British S1 holder whose UK responsibility for healthcare is established. The official BOFiP guidance cites the decision and says that a foreign pension may be included where France is the competent state and the treaty does not exclude French taxation.
Earlier reasoning must also be read in context. In CAA Lyon, 17 March 2022, no. 20LY01439, concerning German and French pensions, the court stated that persons within the coordination rules “ne sont soumis qu’à la législation d’un seul Etat membre”. It nevertheless rejected the claimant’s appeal because she also held a French pension and was therefore subject to French legislation under the facts of that case. The decision is a useful illustration of the one-state principle and the importance of the French pension, but it is not a direct ruling on a UK State Pension after Brexit.
The correct conclusion is deliberately narrow. If France is the competent state and the UK pension is taxable in France, CSG, CRDS and possibly CASA may be lawful even though the pension is foreign. If the United Kingdom is the competent state for healthcare, the S1 covers the disputed period and the pension is otherwise within the French tax base, the claimant may have a serious argument that the French affiliation condition was not satisfied. If the treaty excludes French taxation or the assessment uses the wrong pension classification, a separate ground may exist. The result depends on the complete file.
II. How can a British pensioner challenge an incorrect deduction or tax assessment?
A. Which notices, forms and proof should you send to the DGFiP or the pension payer?
Begin by identifying the act that created the debt. Foreign-pension contributions are commonly shown on a French income-tax and social-contribution assessment, an accompanying schedule or a later notice putting the amount into collection. Note the tax year, assessment reference, date of notification, amount of the pension used, CSG rate, CRDS amount, CASA amount and the service named on the notice. Download the full notice rather than relying on a bank debit. The legal route and deadline depend on whether the amount was assessed by role, paid without a role, pre-computed on a French pension or deducted by a payer.
If the DGFiP assessed the foreign pension contributions, address a formal réclamation contentieuse, meaning a formal tax claim seeking correction or repayment, to the tax service identified on the notice. A message saying “I have an S1, please remove this” may start a conversation but may not preserve every argument or clearly request restitution. The claim should state the year, the amount challenged and the exact relief sought: cancellation, reduction, repayment, correction of the rate, or correction of the foreign-pension base. Use the secure messaging service in the French tax account when available, and preserve the acknowledgement showing the date of submission.
Article L. 190 of the Tax Procedures Code defines the contentious route by reference to “la réparation d’erreurs commises dans l’assiette ou le calcul des impositions” and to the benefit of a right arising from legislation or regulation. That wording fits several possible grounds: the administration treated UK healthcare responsibility as French affiliation; it ignored a valid S1; it used the wrong treaty classification; it included a pension that France may not tax; or it applied the wrong CSG rate or base. Pick the ground that the evidence proves rather than listing every possible objection.
The evidence bundle should be chronological and indexed. Put the S1 first, with all pages and the date of issue. Add the letter or electronic record showing registration with the CPAM, any replacement or renewal, and correspondence with the NHS Overseas Healthcare Service or the competent UK institution. Add the UK State Pension award letter, payment schedule and any document describing the pension as a state pension rather than a private or public-service pension. If the UK institution has stated that the UK remains responsible for healthcare costs, include that statement and identify the period to which it relates.
The second group of documents concerns France. Include the tax-residence evidence, French tax returns, the full notice, the calculation of the foreign pension and proof of the amount paid. If you had no French pension or French employment, say so expressly and support it with the relevant pension records and employment history. If you did have a French pension, do not conceal it: explain its amount, start date and the competent-state analysis. The 2024 Conseil d’État decision shows why a French pension can change the result in a multi-pension case.
The third group concerns the treaty. Attach the pension provider’s classification, the relevant pages of the France–UK convention and the calculation showing why France may or may not tax the income. The French tax authority’s page on foreign pensions advises taxpayers to obtain the nature of the pension from the paying organisation. A letter from the DWP that only confirms payment may not resolve whether a separate occupational or public-service pension is governed by a different treaty article. If more than one UK pension is involved, classify each stream separately.
Use the forms consistently. Form 2047 is the French declaration for foreign income, while form 2042 and its supplementary form 2042-C carry the relevant income-tax and social-contribution entries. Form 2041-GG is the official help document for foreign activity and replacement income subject to CSG, CRDS and possibly CASA. If the tax notice says the foreign pension was entered at the normal rate but the RFR qualifies for the reduced rate or exemption, attach the relevant RFR notices and household-share calculation. That is a rate claim, even if the S1 argument is uncertain.
A useful claim should include a table with one row per year. The columns should show: pension gross amount; income-tax treatment; S1 issue and expiry dates; competent healthcare state; French pension or employment; CSG rate; CRDS and CASA; amount paid; amount requested back; and supporting document number. This makes it possible for the tax officer to correct one year without confusing it with a later year in which the S1 expired or a French pension began.
State the legal proposition in plain English or careful French, then attach the source. For example: the claimant is tax-resident in France, but for the disputed period the UK-issued S1 establishes that healthcare costs were borne under the UK–EU social-security arrangements; the claimant was not otherwise affiliated to the French compulsory health scheme; Article L. 136-1 requires both conditions; and the assessment therefore lacks the social-security condition. If the administration replies that CPAM registration proves French affiliation, ask it to identify the legal basis and the institution responsible for the cost, rather than arguing about the colour of the Carte Vitale.
Send a separate correction to the pension payer only when the deduction was actually made by that payer. The UK State Pension provider will not normally recalculate a French DGFiP assessment. A French pension fund may be responsible for a pre-compted charge on a French pension, but a request to that fund does not automatically challenge a foreign-pension assessment. The notice and the bank statement should identify the correct addressee. Sending the same generic letter to the DWP, CPAM and DGFiP can create delay and inconsistent explanations.
Keep the healthcare dispute separate when necessary. If the S1 was refused, cancelled or not registered, ask the UK institution for a written review and the CPAM for the reason for refusal. That administrative step may produce the evidence needed for the tax claim, but it does not suspend the tax deadline. The tax claim should be filed protectively if the deadline is approaching, with a clear statement that further S1 evidence will follow. A later document can supplement a timely claim; it cannot reliably revive a claim filed after the statutory period.
B. What deadline and court route apply after a French refusal?
Calculate the deadline from the notice and the type of charge. Article R*196-1 of the Tax Procedures Code generally links claims for taxes other than local direct taxes to 31 December of the second year following the relevant event, such as the placing of the assessment into collection, the notification of an assessment notice or the payment of tax where there is no role. Special rules can apply to withholding, advance payments and later notices. For a charge shown on a 2026 assessment, 31 December 2028 may be the ordinary reference date, but the exact notice and event must control.
Do not confuse the tax claim period with the time to bring proceedings. The first task is the administrative claim. The claim should be received by the administration before the deadline, and you should keep proof of transmission, the complete text and all attachments. If the service asks for more documents, answer promptly and preserve the request. If you file online, take a screenshot or download the acknowledgement. If you use registered post, retain the receipt and delivery evidence. The date on which an adviser drafts a letter is not the date on which the administration receives it.
The French administration may grant the claim, reject it, grant only a rate correction, or remain silent. A partial decision must be analysed line by line. It may accept the low-income exemption for one year while rejecting the S1 argument for another. It may correct the CSG but leave CRDS and CASA, or it may accept a treaty argument about one pension while taxing another. Ask for a revised assessment and repayment statement, not only a general assurance that the file has been “updated”.
If the response is unsatisfactory, Article L. 199 of the Tax Procedures Code provides that an administrative decision on a contentious claim that does not give full satisfaction may be brought before the tribunal administratif, the administrative court, for direct taxes and similar turnover taxes. The court will examine the assessment, the legal classification, the evidence and the amount. It will not treat the existence of an S1 as a substitute for proving the exact period, the competent state and the absence of a contrary French affiliation.
The court deadline must be checked on the decision and its appeal instructions. Article R. 421-1 of the Code of Administrative Justice states: “La juridiction ne peut être saisie que par voie de recours formé contre une décision” and normally refers to two months from notification or publication of the challenged decision. A tax dispute is also governed by procedural rules specific to the Tax Procedures Code. The date of receipt, the authority that decided the claim, the assessment years and the amount in dispute must be verified before filing.
A court file should present the issue as a sequence rather than a slogan:
- the claimant was resident in France for tax purposes, or the administration says so;
- the UK issued an S1 for the disputed period and identified the UK as responsible for healthcare;
- the S1 was registered in France only to access care under that responsibility;
- there was no French pension, French activity or other fact transferring competence to France, or the administration has not proved one;
- the UK State Pension was classified under the correct France–UK treaty article;
- the assessment applied Article L. 136-1, Article 14 of Ordinance no. 96-50 and, where relevant, Article L. 137-41 without establishing the French affiliation condition; and
- the amount paid and the requested repayment are demonstrated by the notices and bank evidence.
The counter-argument must also be anticipated. The administration may say that a French pension makes France competent, that the claimant worked in France, that the S1 covered a different period, that the S1 was not valid for the pensioner’s category, or that the treaty allows France to tax the pension. It may rely on the BOFiP position that foreign pensions are subject to contributions where the taxpayer is French-resident, affiliated to a compulsory French health scheme and not protected by a treaty exclusion. A serious claim answers each point with a document and a date.
Do not rely on the older idea that contributions must always be capped at the French pension. The Conseil d’État’s decision no. 473997, read with the BOFiP update of 11 August 2025, rejects an automatic cap in the facts it decided. The decision does not eliminate the threshold question of which state is competent. It means that once France is established as the competent state, the claimant cannot assume that only the French pension can be used in the base. The stronger UK argument is therefore usually about competence, treaty allocation or a calculation error, not an unqualified request to cap every foreign pension.
Equally, do not claim a refund merely because the claimant holds a UK passport or lives in France under a Withdrawal Agreement residence card. Immigration status, tax residence and social-security competence are different legal classifications. A British national can have a French residence card, be French tax-resident, hold a UK S1 and still need to prove how those facts interact for the particular year. The documents must be read together, and the claim should avoid saying that Brexit itself makes French CSG and CRDS unlawful.
Payment and enforcement require a separate decision. A tax claim does not automatically suspend collection. If the amount is substantial, ask the tax service about the available suspension or payment arrangements and take advice before withholding payment. A request for a payment facility is not an admission that the assessment is correct, but it should be drafted so that it does not replace the legal claim. Keep the right to challenge the principal, the rates and any late-payment additions distinct.
For a British pensioner in Paris or elsewhere in France, the competent tax service is identified by the notice and tax account, not selected solely because the person speaks English or once lived in London. A lawyer can help translate the S1 and DWP documents into a French administrative file, calculate the year-by-year amount, identify the applicable treaty article and preserve the court route. The evidence and deadline remain the same whether the claimant lives in Île-de-France, Brittany, the Dordogne or another French region.
The practical outcome may be a full refund, a partial refund, a lower CSG rate, removal of CASA, correction of the pension classification, or confirmation that the assessment is lawful. A precise claim is successful even when it narrows the dispute: it tells the administration which amount is challenged and why. It also prevents the common mistake of treating healthcare registration as an all-purpose tax exemption or, in the opposite direction, treating every CPAM registration as proof of French social-security affiliation.
Conclusion
A UK State Pension paid to a British resident in France is not automatically outside French CSG and CRDS, and an S1 is not automatically irrelevant. The decisive question is whether, for the disputed period, the claimant was both tax-resident in France and covered by a compulsory French health-insurance scheme for the purpose of Article L. 136-1. A UK-issued S1, its registration record and confirmation of UK healthcare responsibility can support a challenge, particularly where there is no French pension or French activity. The tax treaty and the pension’s precise classification must be checked at the same time.
The recent decision CE, 25 October 2024, no. 473997 makes the evidential distinction more important: if France is competent, foreign pensions may be included in the contribution base without an assumed cap; if France is not competent, the administration must still establish the statutory basis for the charge. File a timely, quantified réclamation contentieuse with the S1, UK healthcare evidence, pension classification, tax notices, RFR documents and a year-by-year calculation. If the DGFiP refuses, preserve the administrative decision and check the tribunal-administratif deadline immediately.
Need a quick opinion on your case
If your UK State Pension has been assessed for CSG, CRDS or CASA in France, we can review the S1, your pension classification, the tax notice and the applicable year. You can arrange a telephone consultation within 48 hours with a lawyer from the firm to identify the competent state, calculate the amount in dispute and prepare the appropriate administrative claim.
Call Maître Reda Kohen on +33 6 46 60 58 22, or use the contact form for Kohen Avocats.