Posting an employee abroad: A1 certificate, payroll and obligations

Quick answer. Posting an employee means sending them on assignment abroad while keeping their French employment contract and French social-security affiliation. Within the European Union, the European Economic Area and Switzerland, this is evidenced by the A1 certificate (Regulation EC no. 883/2004), to be requested from Urssaf before departure and valid for up to 24 months. Payroll stays French. It is not to be confused with expatriation, where the employee switches to the local scheme. Outside the EU, posting relies on one of France's bilateral social-security agreements or on membership of the Fund for French Nationals Abroad.

Sending a staff member to a site, a trade fair or an assignment abroad has become common, even for SMEs. But one question always arises: which social-security scheme does the employee remain attached to during the assignment? The answer drives contributions, cover and formalities. Posting keeps the employee on the French scheme; you just have to meet the conditions and distinguish it from expatriation, as we detail in our matrix on expatriate, posted or inbound.

The two notions are often confused, yet they carry very different consequences.

• Posting keeps the employee on a French employment contract and on the French social-security scheme. It is temporary and suited to limited-duration assignments.
• Expatriation attaches the employee to the local social-security scheme of the host country; they lose French cover, save for voluntary membership of the Fund for French Nationals Abroad. It suits long assignments.

The choice is not free: it depends on duration, country and organisation. Payroll, social cover and taxation flow directly from it.

The A1 certificate (formerly E101) confirms that an employee posted within the EU, the EEA or Switzerland remains subject to French social-security legislation during the assignment. It rests on the principle of a single applicable legislation set by Regulation EC no. 883/2004: an employee is subject to only one scheme at a time.

• Who requests it? The employer, from Urssaf (via net-entreprises), before the employee's departure.
• What duration? Up to 24 months. Beyond that, the employee must in principle join the host country's scheme, save for an extension (derogation), which is not automatic.
• What is it for in practice? To avoid dual affiliation and to prove, in a check in the host country, that contributions are paid in France. The employee must be able to present it.

During the posting, the French contract continues: payroll stays French, with French social contributions maintained, as for the employer's payroll obligations generally. Two points of vigilance are added, however:

• Local labour law. Even when posted, the employee benefits from a "hard core" of host-country rules (working time, minimum wage, safety) under the European rules on posted workers.
• Taxation. Income tax follows a logic distinct from social security: it depends on the applicable tax treaty, regardless of the A1 certificate.

1. Qualify the assignment. Check that the situation is indeed a posting (temporary assignment, maintained link with the French employer) and not expatriation.
2. Request the A1 certificate before departure. The request goes to Urssaf; never let an employee leave for the EU, EEA or Switzerland without an A1.
3. Keep payroll French. Continue the contract and contributions in France, and organise the tracking of assignment costs.
4. Check local labour law. Identify the hard core applicable in the host country and the cover of risks (accident, health).
5. Anticipate taxation. Analyse the country's tax treaty to determine where the income will be taxed and avoid double taxation.

The assignment outside the EU. Outside the Union, the EEA and Switzerland, posting relies on one of the bilateral social-security agreements concluded by France. Without an agreement, keeping the French scheme remains possible, but dual contribution in the host country is not ruled out: membership of the Fund for French Nationals Abroad secures the cover.

Remote work from abroad. An employee working remotely from another country is not automatically a posted worker: the more complex situation is covered in our article on working remotely from abroad.

The long assignment. Beyond 24 months in the EU, or for a lasting assignment, expatriation or setting up a foreign subsidiary often becomes more suitable.

• No departure without an A1. In the EU, the EEA and Switzerland, the absence of an A1 certificate exposes you to penalties in checks in the host country.
• Anticipate the lead time. The request is made before departure: do not handle it after the fact.
• Don't confuse social and tax. The A1 settles social security, not income tax, which depends on the tax treaty.
• Respect the local hard core. The host country's labour law applies in part, even when posted.
• Watch the duration. Beyond 24 months in the EU, the situation changes: anticipate the switch or the extension request.

Recently, an industrial SME consulted us about sending two technicians to a several-month site in an EU country. The initial reflex was to "deal with it later". We instead handled the matter upstream: qualifying the assignment as a posting, requesting the A1 certificates before departure, keeping payroll French and checking the local labour-law hard core. The posting was thus secured, and dual contribution avoided. Without an A1, a check on the site would have exposed the company to penalties and a costly adjustment.

Our conviction, as accountants registered with the Ordre, is that international mobility is prepared, not caught up after the fact. Posting is a simple, effective tool for temporary assignments, provided the sequence is respected: qualify, request the A1, keep payroll, check the local, anticipate the tax. This is exactly the kind of file we handle with our social and payroll team.

Hayot Expertise advice. Before any departure abroad, ask yourself three questions. Is the assignment a posting or expatriation? Was the A1 certificate requested before departure (in the EU, EEA, Switzerland), or the bilateral agreement identified (outside the EU)? Has the income tax been analysed in light of the applicable treaty? Handle these points upstream, never after departure: a well-prepared posting avoids penalties and double taxation.