You hired your team at home, in London, New York, Dubai or Singapore, and now business calls you to France: a client to serve in Paris, a subsidiary to support in Lyon, a construction site to supervise in Saint-Denis. Your first reflex is to send one of your own employees to do the job. That reflex is legally possible, but France treats it as a regulated operation called secondment, known in French as détachement. It is neither a local hire nor a business trip, and confusing the three categories is the most expensive mistake a foreign employer can make. Before your employee starts work on French soil, you must file an online prior declaration on the SIPSI portal, the Système d’information sur les prestations de service internationales, which is the official posting-declaration system run by the Ministry of Labour, appoint a representative based in France, secure proof of social security coverage with an A1 certificate, and guarantee French minimum pay and working-time rules from day one. Miss one of these steps and the labour inspectorate, called the inspection du travail, can suspend your service on the spot, while administrative fines run to 4,000 euros per posted worker. This guide explains, in the order a foreign founder actually faces them, how to qualify a genuine posting, how to declare it, what rights to guarantee while your employee works in France, and what happens when your A1 certificate is challenged.

It complements our general guide for foreign founders on setting up a company in France, from the bank account and the Kbis to VAT and the first hire, and goes one step further: you already have a company abroad, and you want to put your own people to work on French territory without creating a French entity first.

I. How do you lawfully send your employee to work in France?

A. Is your operation a genuine secondment (détachement) or a disguised local business?

French law starts with a strict definition. Article L. 1261-3 of the Labour Code, called the Code du travail, provides: “Est un salarié détaché au sens du présent titre tout salarié d’un employeur régulièrement établi et exerçant son activité hors de France et qui, travaillant habituellement pour le compte de celui-ci hors du territoire national, exécute son travail à la demande de cet employeur pendant une durée limitée sur le territoire national dans les conditions définies aux articles L. 1262-1 et L. 1262-2 .” Four conditions already appear in that single sentence, and each of them is checked by inspectors: your company must be genuinely established and active outside France, the employee must normally work for you outside France, the posting must last a limited time, and the operation must fit one of the three legal patterns.

Those three patterns are listed in article L. 1262-1 of the Labour Code: “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 posting is then carried out in one of three ways: for your own account and under your direction, under a contract signed with a French client receiving the service; between establishments of the same company or between companies of the same group; or for your own account without any contract with a recipient, for example when you send a technician to install your own equipment. A separate provision, article L. 1262-2 of the Labour Code, covers temporary-work agencies established abroad that post agency staff to a user company in France. In practice, most foreign founders use the first or the second pattern: a service contract with a French customer, or an intra-group posting to their French subsidiary, known as a filiale, or to their French branch, known as a succursale.

The contract of employment with the home company must exist and must survive throughout the posting. That point matters because the most common trap is the posting that slowly turns into a local job: the employee stays for years, takes orders only from the French team, is paid or promoted by the French entity, and the home company becomes an empty shell. France answers that trap with article L. 1262-3 of the Labour Code: “Un employeur ne peut se prévaloir des dispositions applicables au détachement de salariés lorsqu’il exerce, dans l’Etat dans lequel il est établi, des activités relevant uniquement de la gestion interne ou administrative, ou lorsque son activité est réalisée sur le territoire national de façon habituelle, stable et continue.” The same article adds that prospecting for clients or recruiting staff on French territory also excludes the posting regime, and that in those situations the employer becomes subject to the whole French Labour Code, as if it were established in France. A letterbox company abroad cannot therefore lend staff permanently to a French business under the cover of successive postings.

The Cour de cassation, the highest French court for civil, commercial, social and criminal matters, illustrated both sides of this line in a widely discussed ruling of 5 April 2023, appeal number 21-21.318, available at the official record of the Cour de cassation. An employee hired in Italy in 1979 by the company Leonardo Finmeccanica had been posted to France to the GIE ATR, a groupement d’intérêt économique, meaning an economic interest grouping, since 1 July 1995. In March 2016 the Italian company ended the posting and ordered him back to Italy, then dismissed him for gross misconduct, called faute grave, when he did not return. The employee argued that twenty-one years of continuous posting could not be temporary, that the posting was unlawful, and that he had in reality become an employee of the French host entity, asking the court to recognise an employment contract with the GIE and to order his reinstatement.

The Social Chamber rejected the claim. It recalled the rule in these 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.” It then held that an irregular posting does not by itself create an employment contract with the French host: “le non-respect, par l’employeur étranger, des règles relatives au détachement, sur le territoire national, d’un de ses salariés, n’a pas pour effet de voir reconnaître la qualité d’employeur à l’entreprise établie sur le territoire national et bénéficiaire dudit détachement”, confirming its earlier ruling of 9 January 2013, appeal number 11-11.521. On the facts, the court noted that pay had always been handled by the Italian company, which issued every payslip, that the employee received a yearly posting allowance of 30,000 euros, housing-tax coverage, return travel to Italy and bonuses calculated on the Italian company’s results, that he accepted a long-service medal from the Italian company for thirty-five years of service, and that his promotions were managed from Italy, while the discipline that ended the relationship, the recall order and the dismissal, came from the Italian employer. The daily instructions of the French host were, in the court’s words, inherent to performing a posting mission and did not prove a relationship of subordination, called lien de subordination, with the host.

Foreign employers should read that decision as both reassurance and warning. Reassurance, because a posting that keeps a real link with the home company, with home-country pay, home-country career management and home-country discipline, survives even a very long duration. Warning, because the employee’s lawyers will hunt for every sign that the link has snapped: salary top-ups decided in Paris, appraisals run by the French manager, a French disciplinary warning, or a posting renewed by tacit agreement for years without a return date. Keep the link visible and documented: a written intra-group secondment agreement stating the mission, its duration and its end date, payslips issued and paid from abroad, a return ticket or return plan, and a genuine activity of your company in its home state. European rules also extend the package of French law applicable to long postings, so have counsel check the current version of article L. 1262-4 of the Labour Code before any renewal beyond twelve months.

B. How do you file the SIPSI declaration and appoint your representative in France?

Once the posting is genuine, it must be declared before it starts. Article L. 1262-2-1 of the Labour Code states: “L’employeur qui détache un ou plusieurs salariés, dans les conditions prévues aux 1° et 2° de l’article L. 1262-1 et à l’article L. 1262-2 , adresse une déclaration, préalablement au détachement, à l’inspection du travail du lieu où débute la prestation.” The same article requires the employer to appoint a representative of the company on French territory, who acts as the contact person for the control authorities during the whole service. The Ministry of Labour says the same in plain terms on its official SIPSI page: “Tout employeur établi hors de France qui détache des salariés sur le territoire français doit transmettre avant le début de son intervention en France une déclaration préalable de détachement ou une attestation de détachement à l’inspection du travail du lieu de réalisation de la prestation.” The declaration is filed online through the SIPSI teleservice at sipsi.travail.gouv.fr, which the Ministry presents as a multilingual portal, in French, English, German, Italian and Spanish, that reduces redundant entries and checks information automatically. The official page is published at travail-emploi.gouv.fr.

The declaration is detailed, and that is deliberate: it lets inspectors target controls before anyone sets foot on site. For postings between establishments or companies of the same group, article R. 1263-4 of the Labour Code lists what must be sent: the company name, addresses, legal form, VAT identification number or equivalent registration, the identity of the directors, the successive places of work, the start date and expected end date, the nature of the services, and for each posted employee the name, sex, dates and places of birth, home address, nationality, professional qualification, job performed during the posting and the hourly rate of pay applied in France. Declare every posting separately, update the declaration when dates, places or staff change, and file before the first day of work, not after the inspector arrives. Transport activities use a specific attestation rather than the standard declaration, so road-haulage companies should check the dedicated transport procedure instead of the general form.

Two related duties are often missed by foreign founders. First, the representative in France must be designated inside the declaration itself and the designation covers the whole posting period, as article R. 1263-2-1 of the Labour Code provides. Choose someone reachable, who speaks French, keeps the documents and answers the inspection: a lawyer, an accountant, or your French subsidiary’s manager. A representative who never answers is treated almost like no representative at all when the fine is calculated. Second, your French client has its own legal duty. Under article L. 1262-4-1 of the Labour Code, the client or project owner who hires a service provider posting workers must check, before the posting starts, that the provider has completed the declaration and appointed its representative. If the provider hands over no copy of the declaration, the client must itself file a declaration with the labour inspectorate within forty-eight hours of the start of the posting. In practice, every serious French customer will therefore ask you for your SIPSI receipt, called accusé de réception, before your employee enters the premises, and the Ministry confirms that the client can access its providers’ receipts by creating its own SIPSI account. Prepare the receipt as carefully as your commercial proposal: no receipt, no access to the site.

II. What does France impose while your posted employee works on French soil?

A. What pay, hours and papers must you guarantee when the inspector walks in?

From the first hour of work in France, your posted employee benefits from a hard core of French protections. Article L. 1262-4 of the Labour Code guarantees the posted worker equality of treatment with employees of companies in the same sector established in France, across individual and collective freedoms, non-discrimination, maternity and paternity leave, working time, holidays, pay and health and safety. Three items dominate every inspection: working time, pay, and documents.

On working time, France applies its daily and weekly maximum hours, its daily rest of at least eleven consecutive hours and its weekly rest, plus paid annual leave and public holidays under the conditions of the sector. Night work, Sunday work and overtime follow French thresholds, and overtime triggers French pay uplifts. If the labour inspector finds a serious breach, such as no daily rest, no weekly rest, excessive hours, unpaid minimum wage, or working or housing conditions incompatible with human dignity, article L. 1263-3 of the Labour Code authorises the authority to order the suspension of the service, and work stops until the breach is fixed. Read article L. 1263-3 of the Labour Code before any posting in construction, logistics or hospitality, where hours drift most easily.

On pay, the posted employee must receive at least the French statutory minimum wage, called the SMIC, which stands for Salaire minimum interprofessionnel de croissance, and the minimum set by the applicable sector-wide collective agreement, called the convention collective, including overtime uplifts and allowances that form part of pay. The home-country salary can be higher, and often is for senior profiles, but it can never be lower than the French floor for the job actually performed. State the hourly rate in the SIPSI declaration honestly, pay it, and keep proof. Posting allowances paid to reimburse real expenses for travel, housing or food are not pay, while flat allowances with no supporting expense can be reclassified as pay by the inspector, which creates underpayment for the whole posting period. For third-country nationals, meaning citizens of states outside the European Union, check separately that the employee holds a work authorisation valid for France; the posting declaration never replaces immigration law.

On documents, the inspector asks for papers on the spot, in French. Article R. 1263-1 of the Labour Code requires the foreign employer to keep the posting documents at the workplace, or with its French representative if keeping them on site is materially impossible, and to show them immediately at the inspector’s request: the employment contract or equivalent, any work authorisation for third-country nationals, proof of a medical examination equivalent to the French one, and the records that prove pay and hours. Read article R. 1263-1 of the Labour Code with your representative and prepare the file before departure. Everything must be translated: “Les documents mentionnés à l’article R. 1263-1 sont traduits en langue française.” And for companies outside the euro area, the same article adds: “Pour les entreprises qui ne sont pas établies dans un Etat membre de l’Union européenne dont la monnaie est l’euro, les sommes sont converties en euros.” Payslips in dollars or pounds with no French translation are, for the inspector, the same as no payslips.

Social security runs on a parallel track. As long as the posting stays within the European coordination rules, the employee keeps the home state’s social security cover and the employer keeps paying contributions at home, provided an A1 certificate has been issued by the home institution before or at the start of the posting. The A1 is a portable document that proves which state’s legislation applies, and the French authorities explain the procedure through the CLEISS, the Centre des liaisons européennes et internationales de sécurité sociale, at cleiss.fr, and through the URSSAF international-mobility service, the Unions de recouvrement des cotisations de sécurité sociale et d’allocations familiales, at urssaf.fr. Request the A1 early, because home institutions can take weeks, carry a copy on site with the SIPSI receipt, and never confuse the two papers: the SIPSI declaration proves you informed French labour authorities, while the A1 proves where social contributions are paid. One does not replace the other.

If your posting is based in Paris or elsewhere in Ile-de-France, the Paris region that includes Paris and its surrounding departments, add three local reflexes. First, controls are frequent on Paris construction and renovation sites, on logistics platforms around Roissy and Orly, and on service providers working inside large corporate headquarters, and they are run by the DRIEETS, the Direction régionale et interdépartementale de l’économie, de l’emploi, du travail et des solidarités, the regional authority that supervises the Paris labour inspectorates. Second, your French representative should be reachable on Paris working hours and able to reach any Paris-region site within hours with the French-language file. Third, if the mission involves regulated premises, such as airports, hospitals or public buildings, the site operator will demand the SIPSI receipt, the A1 copy and identity documents days in advance. Build those deadlines into your planning, or your employee will wait at the gate.

B. What happens when your A1 certificate is challenged, and who really pays the fines?

The A1 certificate is powerful but not magic, and the Criminal Chamber of the Cour de cassation drew its exact limits in a leading ruling of 12 January 2021, appeal number 18-86.757, published in the Bulletin and available at the official record of the Cour de cassation. A Portuguese construction company managed by a Spanish national had filed many posting declarations and sent its employees to building sites in France as a subcontractor of French contractors. After an inspection by the labour authorities of the Gironde in September 2013, the manager was prosecuted for concealed work, called travail dissimulé, and the criminal court sentenced him to eight months of suspended imprisonment and a 10,000-euro fine, with damages to the URSSAF of Aquitaine. He argued that the A1 certificates issued by the Portuguese institution covered his workers and blocked any conviction.

The Court restated the European rule first: “les certificats E101, devenus A1, délivrés par l’institution compétente d’un Etat membre créent une présomption de régularité de l’affiliation du travailleur concerné au régime de sécurité sociale de cet État et s’imposent à l’institution compétente et aux juridictions de l’État membre dans lequel ce travailleur effectue un travail, même lorsqu’il est constaté par celles-ci que les conditions de l’activité du travailleur concerné n’entrent manifestement pas dans les cas prévus par le droit communautaire autorisant leur délivrance”, citing the Court of Justice judgment of 27 April 2017 in case C-620/15. But that shield can be lifted for fraud. Following the Court of Justice rulings of 6 February 2018 in case C-359/16 and of 2 April 2020 in the Vueling cases, the French judge may set the certificates aside when the issuing institution, asked to re-examine and withdraw them in the light of evidence gathered during a judicial investigation showing they were obtained or invoked fraudulently, fails to reconsider them within a reasonable time. The fraud must then be fully characterised: objectively, by the failure to meet the conditions for issuing and invoking the certificate, and subjectively, by the intention of the prosecuted person to circumvent or evade those conditions to obtain the attached advantage. The Court recalled its earlier formula: the judge can only set the certificates aside if “il caractérise une fraude constituée, dans son élément objectif par l’absence de respect des conditions prévues à la disposition précitée et, dans son élément subjectif, par l’intention de la personne poursuivie de contourner ou d’éluder les conditions de délivrance dudit certificat pour obtenir l’avantage qui y est attaché”, citing its ruling of 18 September 2018, appeal number 13-88.631.

The same decision then applied the answer given by the Court of Justice on 14 May 2020 in the Bouygues case C-17/19, on a question referred by the Criminal Chamber itself: posting certificates bind the courts of the host state only for social security. The Court of Justice held that “ces certificats ne produisent donc pas d’effet contraignant à l’égard des obligations imposées par le droit national dans des matières autres que la sécurité sociale, au sens de ces règlements, telles que, notamment, celles relatives à la relation de travail entre employeurs et travailleurs, en particulier, les conditions d’emploi et de travail de ces derniers”. In other words, a valid A1 does not excuse the failure to register a real French establishment, to file the prior hiring declaration, or to comply with French employment law. The Court concluded that an employer whose activity is entirely directed at France, run from premises or infrastructure located in France on a usual, stable and continuous basis, cannot rely on the posting regime at all, and producing A1 certificates cannot block a conviction for concealed work based on the missing registration. French courts still impose heavy penalties for organised posting fraud: on 9 June 2026 the Criminal Chamber reviewed a case of “travail dissimulé et marchandage, en bande organisée”, meaning concealed work and unlawful supply of labour committed as an organised gang, in which a company had received a 500,000-euro fine and several managers suspended prison terms, as recorded under appeal number 24-85.090.

Concealed work itself is defined broadly. Article L. 8221-1 of the Labour Code states: “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 ;” Concealment of activity covers running a profit-making business while deliberately avoiding registration or social and tax declarations, as detailed in article L. 8221-3 of the Labour Code, while concealment of employment covers deliberately skipping the prior hiring declaration, failing to issue payslips or understating hours, or skipping pay and contribution declarations, as detailed in article L. 8221-5 of the Labour Code. A foreign company that works permanently in France with posted staff and no registration cumulates both risks at once.

Alongside criminal law, administrative fines strike fast and without a trial. Breaching the declaration, representative or document duties exposes the foreign employer to a fine under article L. 1264-1 of the Labour Code, while the French client that failed its vigilance duty is fined under article L. 1264-2 of the Labour Code. The scale is set by article L. 1264-3 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 same article gives the administration two full years from the breach to act, requires the authority to weigh the circumstances, the seriousness, the good faith and the resources of the offender, and sends any challenge to the administrative court, with no hierarchical appeal: “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.” Five posted workers without a declaration can therefore cost up to 20,000 euros on a first finding, even before any criminal case, and a repeat offence within two years doubles the per-worker ceiling. That arithmetic usually settles, in one meeting, whether the SIPSI paperwork is worth doing properly.

Conclusion

Sending your own employee to France is a five-step operation, and the order matters. First, qualify the mission honestly: a real home-country employment relationship, a temporary mission, and one of the three legal patterns, with no permanent French activity hiding behind the posting. Second, file the SIPSI prior declaration before day one and appoint a reachable French representative inside it. Third, obtain the A1 certificate from the home institution early and carry it with the SIPSI receipt. Fourth, guarantee French working time, minimum pay and French-language documents on site from the first hour. Fifth, hand your French client the SIPSI receipt spontaneously, because the client’s own vigilance duty makes it your gatekeeper. When postings multiply, when missions have no end date, or when your employee hires, signs and manages locally, stop and create the French vehicle instead: a subsidiary or a registered branch with its own payroll puts an end to the posting risks and opens normal hiring, as our founder’s guide explains. Until then, treat every posting as an inspection waiting to happen, and you will pass it.