Receiving a French tax reassessment after Brexit can be alarming, particularly when the notice brings together French income, a UK pension, dividends, property income or a payment already made in the United Kingdom. A British resident may then ask a practical question: can the additional French tax be paid by instalments? The answer is often yes as a matter of administrative negotiation, but a payment plan is not an automatic right and it does not correct an assessment that is legally wrong.

Three routes must be kept separate. A délai de paiement is a request for extra time or an instalment arrangement because the bill cannot be paid on time. A réclamation contentieuse is a formal tax claim challenging the calculation, the facts or the rule applied. A sursis de paiement is an express request to defer the disputed part while that claim is examined. A remise gracieuse is a discretionary remission based on hardship in the circumstances permitted by law. This guide explains how a British resident should choose and combine those routes, what evidence to send, how the France-UK treaty may affect the amount, and what to do if the tax office refuses the request or starts recovery action.

I. Can a British resident in France obtain a French tax payment plan after a reassessment?

A. What should you do when the reassessed bill is payable but you cannot pay it?

The first step is to identify precisely what has been issued and what is already due. A French tax reassessment, or redressement fiscal, may begin with a proposal for rectification, a response to the taxpayer’s observations, a supplementary tax notice, or an avis de mise en recouvrement. The last expression means a formal notice placing a tax debt into collection. These documents do not all have the same legal effect or the same deadline. The heading, tax year, tax type, reference number, date of enforceability and payment date should be recorded before a payment request is drafted.

The nationality of the taxpayer does not decide whether the extra tax is payable. Under Articles 4 A and 4 B of the French General Tax Code, a person whose tax domicile is in France is generally assessed on the whole of their income, whereas a person whose tax domicile is outside France is assessed on French-source income. The Code uses the concept of domicile fiscal, meaning tax residence, rather than British nationality. The factual analysis can include the home, principal stay, professional activity and centre of economic interests.

The 2008 UK-France double taxation convention, in force for the relevant tax periods, then allocates taxing rights for particular categories of income and provides mechanisms to avoid double taxation. It is not a general cancellation of French tax. A pension, dividend, employment income or gain may be treated differently under the convention, but a taxpayer must show which article applies, which state taxed the income, and how the French calculation should be corrected. If the French assessment is correct but the amount cannot be paid immediately, treaty arguments should not be used as a substitute for a payment request.

A payment plan is called a délai de paiement. It is an exceptional arrangement requested from the French tax authority when the taxpayer has a genuine, temporary or exceptional difficulty in paying an established tax debt. The official impots.gouv.fr guidance on payment deadlines says that the taxpayer can make the request after receiving the tax notice and should use the secure online account. The guidance asks the taxpayer to select the payment-difficulty route in the secure mailbox and to explain the circumstances. The administration considers matters such as loss of income, an exceptional event, the relationship between debts and income, the taxpayer’s past behaviour and the efforts made to pay.

For an individual taxpayer, the practical online route is usually the secure messagerie, meaning the encrypted mailbox in the French public-finance account:

• open the secure messaging service in the espace Finances publiques;
• choose the payment or payment-difficulty category;
• identify the reassessed tax, the year and the exact amount;
• attach the completed current questionnaire difficultés de paiement, commonly Form 4805-S-SD, together with a bank account statement or RIB, meaning the French bank-account identification document; and
• propose a realistic instalment schedule and ask for a written response.

The official procedure page confirms the secure-message route and identifies the 4805-S-SD questionnaire and RIB as documents to provide. A British resident who cannot access the online account can contact the tax office shown on the notice or attend a French public-finance centre through an authorised representative. A letter should still contain the same information and should be sent in a way that proves delivery. The form and the online wording may change, so the current version should be downloaded from the official site rather than copied from an old internet forum.

The request should be made as soon as the problem is known. It is weaker to wait until a bank account has been seized, a formal demand to pay has expired or several instalments have failed. A request made before the payment date can show that the taxpayer is trying to deal with the debt, although it does not guarantee that recovery will be paused. The published guidance indicates that ordinary processing can take two months and that a complex file can take longer. It also explains that no response within the stated period is not an acceptance. The taxpayer should therefore continue to protect the position rather than treat silence as permission to stop paying.

Requesting a payment plan does not, by itself, suspend the debt. The applicant should separate:

1. the part of the bill that is accepted and should be paid if possible;
2. the part genuinely disputed on law or calculation; and
3. the cash-flow problem affecting the balance, even if the calculation is accepted.

For example, a British resident might accept €8,000 of additional French income tax but dispute €4,000 because the France-UK treaty credit was omitted. The €8,000 should be dealt with by payment or an ordinary instalment request. The €4,000 should be covered by a properly quantified tax claim and an express request for a sursis de paiement, meaning a statutory stay of payment for the disputed amount. Asking only for “more time” does not necessarily create the legal stay available under the French tax procedure.

The request should not promise an instalment that cannot be met. A proposal of €1,000 per month for a €12,000 balance may be credible if the bank statements show that disposable income is at least that amount after ordinary obligations. A proposal of €3,000 per month when the taxpayer has no such capacity can make the file less persuasive. It is better to show the calculation: regular net income, pension or salary dates, essential expenditure, existing debt payments, available savings, expected receipts and the proposed date for the final instalment. If an asset can be sold or a payment is expected, explain when it will be available rather than presenting it as current cash.

A payment plan also needs to accommodate the taxpayer’s continuing liabilities. A British resident may have monthly withholding on French salary or pension income, social contributions, local property tax, mortgage costs and UK obligations. The schedule should not cause a new French debt while an old one is being paid. It should say how current taxes will be kept up to date and whether a direct debit instruction needs to be changed. The official agreement, if granted, should be retained with the notice, the payment calendar and proof of each instalment.

There is a difference between an agreed payment deadline and mensualisation, which means a standard monthly-payment arrangement normally based on recurring tax rather than a bespoke plan for a reassessment. Joining monthly payment does not necessarily settle an additional assessment already issued. Likewise, a UK HM Revenue & Customs instalment arrangement concerns a UK debt. The GOV.UK guidance on paying HMRC by instalments cannot bind the French tax authority and cannot stop collection of French tax. If the same income is involved in both countries, the two arrangements must be coordinated without confusing their references or deadlines.

If the taxpayer cannot pay because the assessment is wrong, the payment request should say so without blurring the routes. The message can state: “I request a payment arrangement for the undisputed sum. Separately, I am filing a formal claim and expressly request a stay of payment for the disputed sum.” The wording should then identify the exact amount in each category. That division gives the collection officer a usable request and preserves the legal argument for the assessment itself.

A British resident should also check whether the reassessment concerns income that was never received, income allocated to the wrong year, a pension classified incorrectly, an omitted credit for UK tax, or a failure to apply a treaty rule. The payment difficulty may be real even when the tax is valid, but the evidence can reveal both issues. Sending a bare statement that “Brexit caused the bill” is not enough. Brexit changed residence and reporting practicalities; it did not, by itself, change the basic French procedure for requesting time to pay.

B. Which documents and repayment proposal will the French tax office assess?

The payment file should allow an officer to understand the household and the debt without reconstructing it from scattered attachments. Begin with a one-page chronology. State when the taxpayer moved to France, when French tax residence began or was claimed, when the assessment was issued, when the deadline falls, when the UK income was received, what has already been paid, and what event created the current inability to pay. For a couple, identify the taxpayer to whom the notice is addressed and whether the liability is joint. For an estate or a person acting under authority, attach the document proving that authority.

The core tax documents usually include the reassessment notice, the original return, any proposal for rectification, the taxpayer’s observations, the tax office’s reply, the calculation of principal tax, interest and penalties, and proof of payments. If the assessment relates to an earlier declaration, add the relevant French return and the schedules. If it relates to a UK source, add the UK annual tax calculation, pension or dividend statements, payslips, employer documents and evidence of UK tax actually paid. The UK material is evidence; it is not automatically a reason to erase the French amount.

Bank evidence should cover a sufficient period to show the normal position and the exceptional problem. Useful documents can include:

• French and UK current-account statements;
• statements for savings, investment and pension accounts where they are relevant to ability to pay;
• salary, pension, rental or self-employment income evidence;
• mortgage, rent, utilities, insurance, care, medical and education costs;
• statements for existing priority debts and court-ordered payments;
• evidence of an unexpected loss, illness, separation, death, business failure or delayed sale; and
• proof of any payment already sent to the French Treasury or the UK authority.

The documents should be labelled in English or French and cross-referenced in a short schedule. A pound amount should be accompanied by the date and conversion method used. A statement of “£2,000 available” is not complete if the tax authority cannot see whether that is a current balance, a monthly receipt or a future pension payment. Where the applicant relies on a UK tax calculation, state whether it is a final assessment, an estimate or a payment-on-account figure.

The 4805-S-SD questionnaire asks for information designed to measure the difficulty. The applicant should answer it consistently with the attachments. If the form does not provide enough space to explain a cross-border issue, attach a numbered note rather than leaving the relevant box blank. The note can explain that the taxpayer is British, resident in France, paid or reported particular income in the UK, and is asking for a French arrangement because a single reassessed amount has fallen due at once. This is more useful than a general statement that the taxpayer has “international finances”.

Evidence of good-faith compliance matters. Include proof that current French tax payments are up to date where possible, or explain any arrears. If the taxpayer has continued to make withholding payments but cannot meet the lump sum, say so. If a payment was rejected because a UK bank mandate changed, include the bank’s rejection notice and the steps taken to correct it. If the taxpayer missed a deadline because a paper notice went to an old address, give the date on which the notice was actually received, update the address and avoid claiming that non-receipt automatically cancels the debt.

The proposal should be expressed as a schedule, not a hope. It should state the first payment date, each monthly amount, the final payment, the account from which payment will be made and what will happen to current tax. If the applicant can pay a lump sum immediately, say how much and provide proof that it is available. If the proposed payment depends on a house sale, inheritance or pension transfer, identify the risk and offer an interim amount. A tax office is more likely to be able to decide a file that contains a workable alternative than one that merely describes distress.

The taxpayer should ask three questions in writing: whether the request has been accepted, whether the collection account has recorded the schedule, and whether any existing enforcement measure will be suspended or withdrawn. Until the written position is clear, keep funds available and do not cancel a debit on the assumption that the arrangement has been granted. A payment made under an agreed schedule should carry the correct tax reference. Keep bank confirmation, because a debit that leaves a UK account can take time to appear on the French account.

A refusal of an instalment arrangement does not prove that the reassessment is correct. The officer deciding collection may have considered only ability to pay. Conversely, a grant of time to pay does not prove that the calculation is correct. The taxpayer should continue to analyse the notice and preserve any objection deadline. The payment route solves timing; it does not replace the legal route.

The consequences of late payment should be calculated rather than ignored. Article 1730 of the General Tax Code provides that late payment of the listed taxes gives rise to “une majoration de 10 %”, a 10% surcharge, and its current text refers to amounts not paid within 45 days of collection of the role or notification of the collection notice. The exact trigger depends on the tax and the notice. A request for time does not automatically remove that surcharge.

Article 1727 of the General Tax Code also states that a fiscal debt not paid within the legal period gives rise to “un intérêt de retard”, late-payment interest, subject to the detailed rules in the article. The notice may show several components that should not be treated as one negotiable figure. Principal tax, late interest, a late-filing penalty and a payment surcharge may have different legal treatment. A separate remission request may be relevant to some penalties or interest, but it is not an automatic consequence of receiving an instalment plan.

If the amount is large, the taxpayer should take advice before offering security or selling an asset. A family member’s property, a French bank balance or an investment portfolio can raise ownership, valuation and enforcement questions. A proposed plan should not accidentally create a new guarantee or admission beyond what the taxpayer intends. Any French document to be signed should be translated or explained before signature, especially where it contains an acknowledgement of debt or a waiver.

II. How can a British resident challenge a French reassessment while seeking instalments?

A. What is the difference between a tax claim, a stay of payment and a remission?

A formal challenge is a réclamation contentieuse, meaning a claim asking the tax administration to correct an assessment. It should be used when the taxpayer disputes the amount, the factual basis, the tax residence analysis, the classification of income, the treaty treatment, the available credit, the year of assessment or the legality of a penalty. The official impots.gouv.fr claim guidance draws the central distinction: difficulty paying is not itself a tax claim, while disagreement with the calculation or with the rule applied is a reason to file one.

Article L190 of the French Tax Procedures Code places claims seeking correction of errors in the tax base or calculation within tax litigation. Its wording refers to “la réparation d’erreurs commises dans l’assiette ou le calcul des impositions”, the correction of errors in the basis or calculation of the taxes. A claim should identify the tax, period, notice, contested amount, legal grounds, factual explanation, documents and precise outcome requested. “I disagree with the bill” is not a sufficient cross-border analysis. The letter should show the calculation that the taxpayer says is correct.

The time limit must be checked against the notice and the type of tax. The current Article R*196-1 of the French Tax Procedures Code says, in its opening words, “Pour être recevables, les réclamations”, meaning that the time limit is a condition of admissibility. For the taxes covered by that provision, the claim is generally due by 31 December of the second year following the relevant collection, notice or payment event, subject to the special rules and exceptions applicable to the particular assessment. The page is marked as in force from 30 July 2026. The taxpayer should calculate the date from the official notice rather than rely on a generic internet deadline.

A claim does not normally suspend payment. The official tax authority explains that submitting a claim does not remove the obligation to pay, although the taxpayer can ask for a stay of payment. That request is the sursis de paiement. It should be made expressly in the claim, state the amount or bases of the reduction requested, and identify the exact portion whose payment is being deferred. This is not the same as asking the collection office informally for more time.

Article L277 of the French Tax Procedures Code provides that a taxpayer challenging the basis or amount of the tax may, if the request is expressly made in the claim and the requested reduction is quantified, defer payment of the contested portion and related penalties. The text says “à différer le paiement de la partie contestée”. It also states that enforceability and the limitation period for collection are suspended until a final decision on the claim by the administration or the competent court. The statutory stay is therefore directed to the disputed amount, not to a bill that the taxpayer accepts in full merely because payment is difficult.

The stay has procedural conditions. Article L277 provides for guarantees when the disputed rights exceed the amount fixed by decree. The relevant collection accountant may ask the taxpayer to provide security. Article R*277-1 of the same Code says that the taxpayer has “un délai de quinze jours” from the accountant’s invitation to state the guarantees they undertake to provide. It lists possibilities including a payment into a Treasury holding account, claims against the Treasury, a surety, securities, a mortgage allocation and a pledge of a business. The correct response depends on the amount, the nature of the tax and the security offered.

There is a serious difference between the ordinary payment plan and the statutory stay. An accepted payment plan does not decide whether the tax is lawfully due. A properly made claim with a stay request can suspend enforceability of the disputed part, but the taxpayer may need to provide guarantees. An informal message saying “I cannot pay” may be treated as a hardship request and may not protect the disputed amount. The cover letter should therefore use separate headings: “payment arrangement for the undisputed balance” and “formal claim and request for stay for the disputed balance”.

The Conseil d’État has explained the effect of the stay in decision no. 394903, 4 December 2017. The judgment describes the “suspension de l’exigibilité des impositions en litige”, suspension of enforceability of the taxes in dispute, and holds that the tax cannot be collected during the stay under the conditions considered by the statute. The decision concerned co-debtors, but its practical lesson is broader: the taxpayer should not assume that an unquantified objection has the same effect as the statutory request described in Article L277.

Security requires careful handling. In decision no. 296213, 1 October 2007, the Conseil d’État accepted that a third person’s property could be offered in certain circumstances, provided that “le Trésor soit en mesure de recouvrer sa créance”, the Treasury can recover its debt if the taxpayer defaults. This does not mean that a relative’s house is automatically acceptable. Ownership, consent, the nature of the guarantee and the Treasury’s ability to enforce it must be analysed before a proposal is made.

Decision no. 313190, 10 December 2008, is a warning against assuming that a second offer solves a rejected guarantee. The court held that a later offer can give the taxpayer the benefit of the stay only if it is “explicitement acceptée par le comptable”, explicitly accepted by the accountant, after the first refusal has become final. If the taxpayer receives a refusal, the notice and the date of service should be preserved, and the short procedure before the tax référé judge should be considered promptly. A second proposal should not be treated as self-protecting while the administration remains silent.

The taxpayer may instead ask for a remise gracieuse, meaning a discretionary remission or reduction granted for hardship. This is a different legal route. Article L247 of the French Tax Procedures Code permits the administration to grant a full or partial remission of regularly established direct taxes when the taxpayer is in “l’impossibilité de payer par suite de gêne ou d’indigence”, unable to pay because of financial hardship or indigence. The provision also deals separately with remissions of tax fines, surcharges and certain interest, and it excludes several categories of tax from a remission of principal. The applicant must therefore identify the tax component for which relief is requested.

A remission is not a way to argue that the assessment is mathematically wrong. If the French tax office included the same pension twice or refused a treaty credit that should apply, the primary route is the formal claim. If the amount is correct but a sudden illness, loss of income or an exceptional family event makes payment impossible, the primary route is a payment request and, where the statutory conditions are met, a hardship remission. The two explanations can coexist, but the requested outcome must be clear: correction of the assessment, time to pay, cancellation of a penalty, or a reduction of a regularly established direct tax.

Case law shows why a remission application should contain evidence rather than general assertions. In decision no. 394564, 20 September 2017, the Conseil d’État held that a refusal of a remission can be challenged for specified legal errors, including an “erreur manifeste d’appréciation”, a manifest error of assessment. The court also distinguished the factors used for a remission of principal tax from those used for penalties. The taxpayer should provide a current household budget, assets, debts and the event causing the hardship, while also addressing any relevant compliance history.

In decision no. 419907, 7 March 2019, the court stated that the inability to pay is assessed at the time the administration decides: it “s’apprécie à la date à laquelle elle se prononce”. The financial file should therefore be updated if a long delay occurs. A taxpayer who was unable to pay when applying may have recovered later; a taxpayer whose position deteriorated should send updated evidence rather than assume that the original file will remain accurate.

Decision no. 393830, 10 March 2017, confirms that the possibility of remission for penalties and late interest “n’est pas limitée au seul cas” of inability to pay because of hardship. This does not make remission automatic. It means that the administration must consider relevant reasons when the request concerns penalties or interest, such as good faith, the circumstances of the failure and the way the liability arose. The request should identify whether it concerns principal tax, a surcharge, a late-filing penalty, late interest or several distinct items.

For a British taxpayer, the legal challenge often turns on evidence around residence and the UK source. Useful points to test include the date French tax residence began, whether the French home became the centre of the taxpayer’s life, the treaty residence tie-breaker, whether a UK pension is covered by the pension article, whether UK tax was actually paid, whether relief is available under the convention, and whether the same receipt has been entered twice. The treaty’s official text should be read with the French notice and the taxpayer’s own dates. A UK tax return alone does not establish that France lacks taxing rights.

B. What should you do after refusal, recovery action or a missed instalment?

A refusal should be classified before the next letter is sent. The French tax office may have refused the instalment request because the budget did not show ability to pay, because the request was incomplete, because the taxpayer had not maintained current payments, or because recovery had moved to another service. It may have rejected the remission request, the tax claim, the stay, or the proposed guarantee. Each decision calls for a different response. Ask for the written reason and keep the envelope, secure-message record and date of availability.

If the refusal concerns only the payment plan, a revised request can address the precise weakness. It can offer a larger first payment, a shorter schedule, proof of an incoming sum, or an explanation of why a previous failed debit was technical and has been corrected. It can also ask the departmental tax conciliator to review the practical handling after the ordinary service has been contacted. The conciliator cannot rewrite a valid tax assessment or guarantee a remission, but the official payment guidance identifies that channel when a payment difficulty has not been resolved.

If the refusal concerns the calculation, the taxpayer should not rely on repeated payment-plan messages. Complete the formal claim, quantify the reduction, attach the legal and factual evidence, and expressly request the stay of payment for the disputed amount. Pay or seek a separate arrangement for the balance that is not disputed. If the tax administration later rejects the claim, the decision and the applicable court deadline must be reviewed immediately. A claim can fail because it was late or insufficiently substantiated even where the taxpayer had a plausible treaty argument.

Guarantee refusals create their own urgency. Under the French Tax Procedures Code, a refusal of proposed guarantees can lead to a short procedure before the administrative référé judge, meaning the judge dealing with urgent tax-procedure applications. The statutory page for the stay describes a 15-day period after the registered letter in the relevant situation and a possible ten-per-cent consignment requirement for admissibility. Because the route depends on the tax and the exact notice, the taxpayer should use the wording and date on the refusal, not a copied template. The bank, a relative providing security and the tax accountant should all receive consistent information.

Recovery action is separate from the merits of the assessment. A taxpayer may receive a formal demand, a notice of seizure or a saisie administrative à tiers détenteur (SATD), which is an administrative order directing a bank or third party holding funds to pay the public creditor. Article L281 of the French Tax Procedures Code provides a specific route for recovery disputes. It says that recovery challenges “ne peuvent pas remettre en cause le bien-fondé de la créance”, cannot challenge the underlying merits of the debt. They may concern the form of the recovery act, the obligation to pay, the amount after payments, or enforceability.

This distinction matters in a cross-border case. If a bank has taken the wrong amount after the taxpayer paid, or the recovery act names the wrong person, Article L281 may be relevant. If the taxpayer says that France misapplied the UK-France treaty, that issue belongs in the tax claim, not in a recovery challenge alone. In some cases both tracks are necessary: one to challenge the assessment and one to challenge the way collection was carried out. The letters should state which act is being challenged and should not assume that a recovery complaint automatically pauses the bank’s obligations.

A missed instalment under an accepted plan should be addressed on the same day. Contact the service, explain the reason, make the payment if funds are available and ask whether the schedule remains in force. Do not assume that the next instalment cures the default. A payment-plan agreement may contain its own consequences for a missed payment, and the collection service may revive the full balance or add recovery costs. If the missed payment resulted from a bank mandate or currency problem, attach the bank evidence and show the replacement payment date.

The same discipline applies to a British resident who pays from sterling income. A euro instalment can be larger in sterling when the exchange rate changes. The proposed schedule should include a margin for that risk and a dedicated euro balance where possible. A UK standing order cannot be assumed to arrive on the French due date. When the tax reference is important, the taxpayer should verify the French account after the transfer and retain the confirmation. If a family member pays, identify the taxpayer and tax reference so the payment is allocated correctly.

The following sequence is a sensible working checklist after a French reassessment:

1. download every notice and identify the tax, period, reference, amount and due date;
2. separate principal tax, interest, penalties, accepted amounts and disputed amounts;
3. prepare the residence, UK-income and treaty evidence before writing the legal grounds;
4. submit the payment-difficulty request with Form 4805-S-SD, RIB, budget and a credible schedule;
5. file the formal claim within the applicable deadline if the assessment is disputed;
6. make an express, quantified stay request under Article L277 for the disputed part and respond promptly about guarantees;
7. pay or arrange the undisputed part and maintain current French tax obligations;
8. record every secure message, telephone call, payment and decision; and
9. react immediately to a refusal, demand to pay, SATD, guarantee notice or missed instalment.

The sequence is especially important where a British resident has moved recently. The first French tax return, the tax-number process, treaty residence and the payment of UK income may be connected, but they are not one issue. The firm’s guide to the first French tax return after moving from the UK can be used for the broader arrival context. The present article concerns the narrower question that arises after a reassessment: how to keep collection manageable while preserving a challenge to an incorrect amount.

Before signing an acknowledgement or giving a mortgage as security, verify the amount and the effect on the disputed claim. A plan can be useful even where the taxpayer intends to challenge part of the bill, but a careless admission can complicate the argument. The cover letter should preserve the distinction: payment efforts are made without abandoning the claim; the requested stay concerns only the quantified disputed part; and any security is offered only on the terms expressly accepted by the taxpayer.

Finally, keep expectations realistic. The French administration can grant time to pay, but it is not required to convert every reassessment into a long schedule. A taxpayer who demonstrates a temporary cash-flow event, offers a credible amount, pays what can be paid and supplies complete evidence has a stronger administrative case. A taxpayer who says only that the bill is inconvenient, or who uses a payment request to avoid the claim deadline, risks both collection action and loss of the legal challenge.

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Call +33 6 46 60 58 22 to discuss the notice, the proposed instalments and any treaty or recovery issue.

You can also contact the firm through the online form and provide the tax year, amount, deadline and documents received.

Conclusion

A British resident in France can ask the French tax authority for a délai de paiement after a reassessment, but the request is an administrative solution to a payment problem, not a ruling on whether the tax is due. The application should be early, documented and realistic, with the 4805-S-SD questionnaire, RIB, household budget, cross-border income evidence and a clear schedule.

If the reassessment is wrong, file a réclamation contentieuse and state the amount and legal basis of the correction. If collection of the disputed part must be deferred, request the sursis de paiement expressly under Article L277 and respond to any guarantee request within the applicable time. A remise gracieuse may address genuine hardship or certain penalties, but it does not replace an objection to an incorrect calculation. Keeping those routes separate is the best way to seek manageable instalments without surrendering a valid France-UK tax argument.