When employees are temporarily posted to another EU or EEA country, “where to pay social security constibutions” is one of the first questions that arises. The answer lies in the A1 certificate. This certificate is a document that proves which country’s social security legislation applies to the worker.
What Is the A1 certificate?
The A1 certificate is issued under EU Regulation (EC) No 883/2004 and confirms that an employee remains covered by the social security system of their home country while working temporarily in another EU or EEA country (or Switzerland).
This means that even though the employee is physically working abroad, both employer and employee continue paying social security contributions in the sending country and thus not the host country.
Why Is the A1 certificate important?
Without an A1 certificate, there is no proof that the employee is insured in their home country. This can lead to double contributions in both countries or, worse, to the employee being uninsured during their stay abroad.
For employers, the A1 certificate helps avoid legal disputes and administrative complications with foreign authorities, while for employees, it ensures continued access to benefits such as healthcare and pensions.
The key link between A1 and remuneration
A1 remuneration (A1 verloning) refers to how salary and social contributions are structured when an employee works temporarily abroad under the A1 framework.
Although the employee remains part of the home country’s payroll system, the entire compensation package, including bonuses, allowances and benefits, must still comply with the host country’s minimum labor and remuneration standards.
This means that even if contributions are paid in the home country, the actual working conditions in the host country (e.g. minimum wage, working hours, health and safety rules) must still be respected.
For example:
- A Polish employee posted to Netherlands under an A1 certificate continues to pay social security in Poland.
- However, their pay must meet Dutch minimum wage standards and comply with local labor laws.
The challenges in practice
The complexity arises when salary components differ between countries. What is considered a taxable benefit in one country might not be in another. Employers must therefore clearly document the remuneration structure to demonstrate compliance with both national systems.
Additionally, host-country labor inspectors may review whether employees under A1 conditions are genuinely posted and properly compensated. Incorrect remuneration or undeclared payments can result in penalties or exclusion from contracts.
Recent developments
In recent years, EU member states have increased their scrutiny of cross-border employment. Authorities are paying particular attention to the misuse of A1 certificates and salary dumping practices.
To ensure compliance, companies should maintain transparent documentation, submit applications on time and regularly review pay structures to reflect host-country standards.
The European Commission provides detailed guidance on A1 coordination rules, available here:
- European Commission – Social security coordination
- Regulation (EC) No 883/2004 on the coordination of social security systems
In summary
The A1 certificate is not just a formality. It is a safeguard for both employers and employees.
By understanding how A1 remuneration (A1 verloning) works and ensuring proper documentation, companies can prevent legal and financial risks while maintaining compliance across borders.
Cross-border employment can bring great opportunities, but only when handled with clarity, precision and respect for the rules that keep Europe’s labor market fair and connected.