You run a company in London, New York, Berlin, Dubai or Singapore and one of your clients or subsidiaries in France asks you to send two engineers, three nurses seconded inside your group, or a full team for a six-month installation. You keep paying them at home, you keep their home employment contracts, and you assume that nothing changes because the assignment is temporary. French law sees the situation very differently. From the first day of work on French soil, your posted staff fall under a hard core of French labour rules, you must file an online posting declaration before they start, you must appoint a representative in France, and you must be able to show an A1 social security certificate for each worker. Miss one of those steps and a routine visit by the labour inspectorate, the inspection du travail, or a control by URSSAF, the body that collects French social contributions, can turn into a fine of up to 4,000 euros per worker, a recovery of unpaid contributions, an order suspending your service, and in serious cases a criminal file for concealed work. This guide explains, for a foreign employer with no French payroll yet, when you are really posting workers to France, what the SIPSI declaration, the A1 form and French pay rules require in practice, how inspections unfold, and how you challenge a fine or a recovery from abroad without losing your deadline.
I. How to send your own staff to work in France lawfully while you remain based abroad
Posting, or détachement, covers three everyday patterns for foreign founders: you perform a service in France for a French client with your own team, you move staff between establishments of the same company or the same group, or you send workers to France for your own account without a French client contract, for example to install your product or open a showroom. In each pattern the home employment contract must survive the assignment. That survival is the line between lawful posting and a hidden French hire that should have been declared to URSSAF and given a French contract. Before looking at pay, get the entry paperwork right, because French inspectors check papers first and substance second.
A. When are you really posting workers to France and what must you file on SIPSI before day one?
French law states the starting point in plain terms: “Un employeur établi hors de France peut détacher temporairement des salariés sur le territoire national, à condition qu’il existe un contrat de travail entre cet employeur et le salarié et que leur relation de travail subsiste pendant la période de détachement.” The same Article L1262-1 of the Labour Code then lists the three lawful cases: work for your company under your direction under a contract with a French recipient, movement between establishments of the same business or companies of the same group, and work for your own account with no French recipient. If your people will instead take orders day to day from the French client, work permanently in France, or were hired specifically to work in France with no real activity in the home country, do not call it posting. Labour courts and URSSAF reclassify that as direct French employment, with French dismissal rules, French pay slips and full French contributions. That reclassification is far more expensive than a posting file done properly.
Once posting is the correct box, two prior formalities are mandatory. The posting employer “adresse une déclaration, préalablement au détachement, à l’inspection du travail du lieu où débute la prestation.” That declaration is filed online on SIPSI, the French acronym for the international service provision information system, the official posting declaration portal run by the Ministry of Labour at sipsi.travail.gouv.fr. In practice you create a company account, describe the home company, list every posted worker with identity, home contract dates and qualifications, state the French place of work, start and end dates, working hours, pay rate, accommodation terms when you provide housing, and the details of the French client or host establishment. You file before the first shift, you keep the acknowledgment, and you update the file if dates, place or headcount change. The labour ministry help pages at travail-emploi.gouv.fr on the general posting framework and the the SIPSI portal describe the same sequence, and inspectors treat a missing or late SIPSI receipt as a standalone fine ground even when pay was correct.
The same Article L1262-2-1 of the Labour Code adds a second duty that foreign founders often miss: the posting employer “désigne un représentant de l’entreprise sur le territoire national, chargé d’assurer la liaison avec les agents mentionnés à l’article L. 8271-1-2 pendant la durée de la prestation.” That representative, the représentant en France, must be reachable by the inspection du travail, the DREETS, the regional directorate for employment and labour which supervises the inspectors, and the police or customs officers empowered to check illegal work. The representative holds the SIPSI acknowledgment, pay records, working-time records, A1 certificates, employment contracts and, for non-EU staff, work-permit evidence, and produces them in French or with a French translation on request. A London phone number that never answers is not a representative. Use a French-based lawyer, accountant, client contact with a written mandate, or your French subsidiary manager, with a real address and a duty to forward control letters the same day. Without that chain, a letter sent to a foreign head office that arrives after the deadline still binds you.
If you work through a French client, that client carries its own vigilance duty and will ask for your papers before you arrive. Article L1262-4-1 of the Labour Code provides that “Le donneur d’ordre ou le maître d’ouvrage qui contracte avec un prestataire de services qui détache des salariés, dans les conditions mentionnées aux articles L. 1262-1 et L. 1262-2, vérifie auprès de ce dernier, avant le début du détachement, qu’il s’est acquitté des obligations mentionnées aux I et II de l’article L. 1262-2-1.” In plain English, the French client or main contractor, called the donneur d’ordre or maître d’ouvrage, must check that you filed SIPSI and appointed a representative, and if you did not give them a copy of the declaration, they must file their own backup declaration within forty-eight hours of the start. Expect serious French buyers, especially in construction, logistics, hospitality and industrial maintenance, to block site access until they receive your SIPSI receipt, your representative mandate and your A1 forms. Build that document pack into your commercial timetable, not the night before mobilisation. Founders who are also creating a lasting presence should read our companion guide on setting up a French company as a foreign founder to decide whether repeated postings should become a branch or subsidiary instead.
Practical pack before day one therefore looks like this: home employment contracts showing real prior activity, SIPSI acknowledgment for the exact site and dates, written mandate for your French representative with phone and address, A1 certificates or proof of request for each worker, pay and hours statement aligned with the French applicable rates described below, and accommodation and travel documents if you house the team. Keep everything for the duration plus the limitation period, in a shared folder your representative can open from a phone on site. Inspectors photograph what you cannot produce.
B. What pay, hours and social cover must you guarantee to posted staff working in France?
Posting does not mean home pay for French work. For the first twelve months, France applies the revised posting directive through an equality-of-treatment rule. Article L1262-4 of the Labour Code states that the posting employer “lui garantit l’égalité de traitement avec les salariés employés par les entreprises de la même branche d’activité établies sur le territoire national” for a closed list that includes working time, rest, public holidays, paid leave, health and safety, and, crucially, “Rémunération au sens de l’article L. 3221-3, paiement du salaire, y compris les majorations pour les heures supplémentaires.” That phrase means the posted worker must receive at least the French statutory minimum wage, the SMIC, or the higher minimum set by the French sector collective agreement, the convention collective, that covers the activity performed in France, plus overtime mark-ups, night and Sunday premiums, paid-leave indemnity and the professional-expense refunds for transport, meals and lodging linked to the mission. The service-public.fr posting pages summarise the same hard core, and sector minima are published by the Ministry of Labour by collective-bargaining identifier, the IDCC number.
Three pay traps catch foreign employers. First, allowances only count toward the French minimum if they are real wage, not reimbursement of posting costs. Money that repays the hotel, the flight or the Paris metro pass does not lift pay to the French minimum. Second, overtime is French overtime from hour thirty-six. France works a statutory thirty-five-hour week, and hours above that carry a 25 percent increase for the first eight hours and 50 percent beyond, unless the applicable collective agreement sets a different but still lawful rate. Our guide on overtime for a first French hire while you live abroad walks through the same arithmetic with time-record examples, and the same records are required for posted staff. Third, payslips must be intelligible to a French inspector. A home-country payslip in English showing a monthly lump sum with no hours, no rate and no premium lines invites a finding of underpayment. Produce a French-language posting pay statement that mirrors the French minimum for the job classification, shows base, overtime lines, premiums, leave accrual and expense refunds on separate lines, and reconciles with bank transfers.
After twelve months on the same post, the regime hardens. The same Article L1262-4 provides that beyond twelve months, extendable once to eighteen months on a reasoned declaration before expiry, the employer falls under almost all French labour law except a few listed hiring and contract-formation chapters. In practice a posting that lasts becomes French employment law in full: full dismissal procedure, full staff-representation consultation where thresholds are met, and full application of the sector agreement. Replacing a posted worker by another posted worker on the same post does not reset the clock, because the twelve months cumulate per post. If your roadmap shows multi-year presence, stop renewing postings and hire or transfer under French contracts instead. That choice also simplifies tax residence and permanent-establishment risk, which belong to your tax advice but start with the same headcount facts.
Social security follows a parallel track through the A1 certificate. Inside the European Union, the European Economic Area and Switzerland, a worker who remains affiliated at home during a temporary posting stays under home social security if the posting conditions of EU Regulations 883/2004 and 987/2009 are met, proved by an A1 form issued by the home institution. The A1 creates a presumption that contributions are due at home, not to URSSAF in France, but that presumption only holds while the posting is genuine, temporary and documented. Outside the EU, bilateral social security treaties, where they exist, decide whether dual contributions apply. The French Cour de cassation polices the boundary strictly. In its widely cited 16 October 2025 ruling on foreign employers and URSSAF controls, the Second Civil Chamber holds that “pour rechercher ou constater des infractions de travail dissimulé s’agissant de salariés exerçant une activité en France pour le compte d’un employeur ayant son siège social à l’étranger, les agents de contrôle des organismes de sécurité sociale et des caisses de mutualité sociale agricole, agréés à cet effet et assermentés, vérifient les déclarations qui doivent être faites par l’employeur aux organismes de protection sociale et de recouvrement des contributions et cotisations sociales en vertu des dispositions légales en vigueur en recueillant auprès de l’employeur les documents, quels que soient leur forme et leur support, qui permettent d’établir si l’employeur dispose d’une affiliation à la sécurité sociale française.” Read that as an operational warning: URSSAF inspectors may demand any document, in any form, that proves French or home affiliation, and a missing A1 on the day of control points straight to recovery. Apply for A1 forms weeks ahead, carry the issued forms or the dated proof of application plus home affiliation evidence, and never let a worker start with “A1 pending, we will sort it later.”
Accommodation, travel and documents complete the picture. If you house posted workers, the lodging must meet French decency, safety and density standards, and collective housing triggers prior declarations to the prefecture in some sectors. Transport time, on-call time and night work follow French definitions, not home definitions. Keep on site, in French: SIPSI receipt, representative mandate, contracts, A1 forms, pay and time records, collective-agreement reference with the applied pay grid, and proof of accident insurance covering work in France. That bundle answers 90 percent of inspector questions before they become findings.
II. What French inspectors check on site and how you answer fines and recoveries from abroad
Controls usually arrive without warning on a building site, a warehouse, a restaurant kitchen or during a document audit at your French client. The labour inspector checks SIPSI, representative, pay, hours, rest, housing and the posted workers register. The URSSAF inspector checks affiliation, A1 validity and contribution base. The police, customs or anti-fraud officers check identity, right to work and signs of concealed work. Each writes its own report, but the reports circulate. A labour finding of missing SIPSI often triggers an URSSAF recovery, and a finding of sham posting triggers a criminal referral. Understanding that chain lets you respond once, coherently, instead of fighting three files with three stories.
A. How do labour and URSSAF checks end in administrative fines, suspension and criminal exposure?
The administrative fine is the everyday sanction. Article L1264-1 of the Labour Code states that “La méconnaissance par l’employeur qui détache un ou plusieurs salariés d’une des obligations mentionnées à l’article L. 1262-2-1, au troisième alinéa du II de l’article L. 1262-4, à l’article L. 1262-4-4 ou à l’article L. 1263-7 est passible d’une amende administrative, dans les conditions prévues à l’article L. 1264-3.” In practice that targets missing or defective SIPSI declarations, missing French representative, missing document retention and late long-posting notifications. Your French client faces a mirror risk: Article L1264-2 of the Labour Code makes the client or user company liable when its contractor missed SIPSI duties and the client failed its own forty-eight-hour backup filing or its duty to inform temporary staff of pay rules. That is why French buyers now write posting compliance into subcontracts with termination and indemnity clauses.
The price is set by Article L1264-3 of the Labour Code: “Le montant de l’amende est d’au plus 4 000 € par salarié détaché et d’au plus 8 000 € en cas de réitération dans un délai de deux ans à compter du jour de la notification de la première amende. Le montant total de l’amende ne peut être supérieur à 500 000 €.” The authority weighs circumstances, gravity, good faith, resources and burdens, and the action is time-barred two full years after the breach. Five workers with no SIPSI can therefore mean up to 20,000 euros on a first case, doubled on a repeat within two years, plus one fine per breach type. The DREETS notifies by registered letter or electronic service to the representative and to the foreign head office. From that date short appeal clocks start to run, which is why your representative must forward mail daily.
Beyond fines, the prefect, on a labour inspector report, can order suspension of the service for up to one month when posted workers face grave risk or when core posting rules are repeatedly ignored, and can order closure of accommodation that breaches dignity standards. The client may also be ordered to stop work with a non-compliant contractor. Separately, URSSAF issues a recovery, the redressement, for contributions it considers due in France: French employer and employee shares, surcharges for late payment, and, where concealment is found, the flat-rate uplift for concealed work that can reach 25 percent of the assessment. Our companion guide on URSSAF audits run from abroad details the letter-of-observations and formal-notice sequence that also applies to posting recoveries, including the adversarial reply window you must not waste.
Criminal exposure sits above the administrative layer. French law provides that “Sont interdits : 1° Le travail totalement ou partiellement dissimulé, défini et exercé dans les conditions prévues aux articles L. 8221-3 et L. 8221-5.” under Article L8221-1 of the Labour Code, and that “Le fait de méconnaître les interdictions définies à l’article L. 8221-1 est puni d’un emprisonnement de trois ans et d’une amende de 45 000 euros.” under Article L8224-1. Sham posting is a classic path to that charge: no real home activity, workers hired only for France, permanent presence dressed as rotation, missing prior hiring declarations, no accident cover in France, or A1 forms obtained by misstatement and later withdrawn. The criminal courts look at substance over paper. In the CityJet line of cases on permanent airline bases in France operated under foreign contracts, the courts stressed that a stable base with French-based staff, local equipment and local management points to French employment regardless of the Irish contract label, and in that file the appeal ruling had “déclaré la société CityJet coupable des faits de travail dissimulé et l’a condamnée à une amende délictuelle de 100 000 euros”. Foreign founders who keep a rolling team in France for years under back-to-back three-month postings invite exactly that comparison. If your operation looks permanent, make it permanent on paper too.
Expect inspectors to seize phones, copy rosters, photograph housing, interview workers separately with interpreters, and ask the client who gives daily orders. They compare SIPSI dates with badge logs, transport tickets and site-access records. Gaps of a few days, wrong site address, or a worker on site who is not on the SIPSI list each count. Fix what you can during the visit: produce missing documents the same day, correct the SIPSI entry, translate a payslip, show A1 requests with dates. What you hand over during control often decides whether the report proposes a warning, a fine or a referral.
B. How do you challenge a posting fine, a URSSAF recovery or a service ban from abroad without missing the deadline?
Start with the calendar, because French posting litigation is won or lost on time. The administrative posting fine is challenged before the administrative court, and Article L1264-3 is explicit: “L’employeur, le maître d’ouvrage ou le donneur d’ordre peut contester la décision de l’administration devant le tribunal administratif, à l’exclusion de tout recours hiérarchique.” There is no higher administrative appeal to wait for. The standard two-month period from notification applies, proved by the receipt signed by your representative or by electronic service logs. Docket the date in Paris time, add nothing for distance unless the code expressly grants it for overseas service, and file by Télérecours, the administrative courts online filing system, with a French address for service at your representative or counsel. Ask the judge in the same filing to stay enforcement if payment would cripple the mission, but know that opposition to enforcement does not automatically suspend recovery, because the same article adds that collection follows State-claim rules. Paying under protest while you litigate often costs less than forced recovery with surcharges.
On the merits, administrative judges review both the breach and the amount. Winning lines, in order of strength, are: no posting at all because the workers were genuine business travellers with no provision of services, short intra-group meetings with no productive work in France, or self-employed directors with no employment contract, proved by agendas, tickets and the absence of French client billing; timely SIPSI filing with a clerical error that did not hide the workforce, proved by the portal timestamp, prior identical filings and immediate correction; valid A1 coverage at the control date, proved by issued forms or by a home-institution certificate confirming retroactive coverage where the regulation allows it; pay at or above the French sector minimum once allowances are correctly split between wage and expense refund, proved by a reconciled French-language pay statement, transfer slips and the applicable collective-agreement grid; and disproportionate amount given good faith, small size, immediate cure and clean history, supported by compliance upgrades. Losing lines are: “we did not know,” “the client was supposed to file,” “our home payroll provider said French law does not apply,” or an A1 request filed only after control. The client-vigilance rule in Article L1262-4-1 helps you share civil cost with a negligent client, but it does not erase your own SIPSI duty.
URSSAF recoveries follow a different court but the same discipline from abroad. You reply to the letter of observations within the stated period, usually thirty days, with A1 forms, home affiliation proofs, contracts showing subsisting home employment, timesheets and pay proofs, and you demand the inspector’s evidence for any concealed-work uplift. If a formal notice, the mise en demeure, still issues, you seize the judicial social-security court, now the specially designated judicial court, within the notice period, and you pay or guarantee the undisputed part to preserve credibility. The 16 October 2025 ruling above helps frame that reply: because URSSAF agents may collect any document showing French or home affiliation, your reply should give them that full affiliation story rather than a bare “posted, therefore exempt” assertion. Where an A1 is later withdrawn for fraud following the EU Altun procedure, with prior dialogue between institutions, French courts will enforce the withdrawal. Challenge the withdrawal at the home institution in parallel, and keep both files consistent.
For a suspension or accommodation-closure order, move faster: administrative interim relief, the référé-suspension, within days, showing urgency through stopped billing, perishable works or worker-safety cure already completed, plus serious doubt on legality through fresh SIPSI, compliant housing or corrected hours. For criminal risk, do not volunteer explanations to police without counsel, preserve messages with the home payroll provider and the A1 applicant, and align the labour, URSSAF and criminal narratives through one coordinator. Parallel files with contradictory headcounts destroy credibility everywhere.
Five reflexes from abroad close the loop. First, give your French representative a standing instruction to scan every official letter the day it arrives and to confirm receipt in writing. Second, run a single posting file per mission with SIPSI versions, A1 forms, contracts, pay grids, time records and housing proofs, shared with counsel. Third, calendar every French deadline in Paris time with a forty-eight-hour internal advance, because French courts rarely excuse a foreign-post delay. Fourth, fix forward immediately: corrected SIPSI, French-language pay top-ups with back-pay slips where needed, and a written posting policy for managers who rotate staff. Fifth, decide the structural question once postings repeat: occasional missions stay postings, permanent teams become French hires or a registered presence. That decision, taken early, is what turns a fine-prone rotation into a stable French operation.
Conclusion
Sending your own people to France can remain simple if you treat posting as a real French procedure, not an email to payroll. Check that the home contract genuinely survives, file SIPSI before the first shift, appoint a French representative who actually answers, carry valid A1 forms, and pay at least the French sector minimum with French-readable records. When inspectors visit, produce the full pack the same day and correct what can be corrected. When a fine or a URSSAF recovery arrives, challenge the right decision before the right court within the short French deadline, with consistent evidence across the labour and social files, and cure the operation while you litigate. Handled that way, a French assignment stays what you intended: a temporary mission that wins business and brings the team home, rather than the first page of a concealed-work file.