The document certifying continued affiliation to French social security during a secondment.
The A1 certificate is an essential formality for many secondments. Where applicable, it certifies that a seconded employee remains affiliated to the French social security system during their assignment abroad, helping to avoid double affiliation in certain states.
When does the A1 certificate apply?
It applies under European regulations coordinating social security systems (European Union, European Economic Area and, in some cases, Switzerland) as well as under certain bilateral social security agreements signed by France with other states. Each situation must be assessed based on the destination country, length of assignment, employee status, nature of the activity and the contractual link with the French employer.
Why is it essential?
Without an applicable A1 certificate, a company may face several difficulties: contributing simultaneously in two countries, losing certain social rights, difficulties when the employee returns, higher salary costs, or a reassessment during an audit.
Most common mistakes
Missing A1 certificate where required, late requests to the relevant bodies, poor assessment of maximum secondment durations, incomplete documentation during an audit.
Our support
We help French companies identify applicable agreements, prepare and follow up A1 certificate applications, and secure the entire secondment file in coordination with your HR teams.