Day-to-day accounting, advice and reporting: fast, digital and always within reach.
Reliable insights through independent assurance of figures, systems and ESG information.
Clear tax and legal advice to navigate complex regulations and decisions with confidence.
Guidance on strategic decisions that impact your organisation and private wealth.
Digital solutions that connect data, streamline processes and strengthen your organisation.
Protecting your organisation through risk management, prevention and insurance advice.
by Lise Bouten and Evelien Rummens
European rules on cross-border employment, the posting of workers and A1 certificates are undergoing reform. After years of negotiations, the European institutions took a significant step forward in 2026 towards revising Regulations (EC) No 883/2004 and No 987/2009, which govern the coordination of social security systems across Europe.
The reform aims to make the rules clearer, fairer and easier to apply. It pursues several objectives: promoting fair labour mobility, providing greater legal certainty, reducing administrative burdens, combating fraud and abuse more effectively, and strengthening the protection of citizens' social security rights.
The revision of the European social security regulations is based on five pillars:
Unemployment benefits;
Long-term care benefits;
Access to social benefits for economically inactive citizens;
Family benefits;
The applicable social security legislation for posted workers and those working in two or more Member States.
In this article, we focus on the fifth pillar: the rules for employees and self-employed individuals who work across borders on a temporary or permanent basis.
In principle, anyone performing cross-border work must apply for an A1 certificate from the competent authority. This certificate confirms which social security legislation applies to the person in question.
However, the revision provides for two exceptions under which an A1 certificate does not need to be applied for.
The first exception applies to business trips. These are defined as temporary activities related to the business interests of the employer or self-employed person, without involving the provision of services or the delivery of goods.
The regulations include a non-exhaustive list of activities that may fall under this category, including business meetings, cultural and scientific events, conferences, and seminars.
A second exception applies to short-term cross-border work. Under the revised rules, an A1 certificate is not required if the work lasts no more than three consecutive workdays within a period of thirty consecutive days.
Please note: work in the construction sector is expressly excluded from this exception. For these activities, an A1 certificate is always required.
In addition to the new exceptions, the timing of the application is now regulated more strictly.
Until now, an A1 certificate had to be applied for in advance whenever possible. The revision replaces that wording with a clear requirement: the A1 certificate must be applied for before the start of cross-border work.
For situations in which work is performed in two or more Member States, an A1 certificate may now be issued for a period of up to 24 months, whereas in current practice it was typically issued for 12 months. At the end of this period, a reassessment must be made to determine which social security legislation applies.
The reform also adjusts various conditions for posting. In particular, prior enrollment in the social security system and the rules for successive postings deserve attention.
To be eligible for posting, the person concerned must have been subject to the social security legislation of the home Member State prior to the posting. This period is extended from one month to at least three months. Furthermore, this must be an uninterrupted period of coverage. This condition applies to both employees and self-employed individuals.
The maximum posting period of 24 months remains unchanged. However, for consecutive postings, a mandatory two-month break (cooling-off period) is introduced.
Exceptions to the standard rules remain possible through an agreement between the competent authorities pursuant to Article 16 of Regulation 883/2004. However, such an exception does not constitute an automatic right. It remains subject to the approval of the competent authorities involved.
Acknowledgment of receipt for pending applications: If an A1 certificate cannot be issued immediately, the competent authority must now provide an acknowledgment of receipt for the application.
Binding deadlines for data exchange: In addition, clear deadlines are being introduced for cooperation and the exchange of information between the competent authorities of the Member States.
Requests for information must be responded to within 35 business days.
If an authority has doubts about the validity of an A1 certificate, the competent institution must respond within 30 business days.
Not all of the new provisions will take effect at the same time. A limited number of changes will take effect immediately, specifically on the first day of the month following the publication of the regulation in the Official Journal of the European Union.
However, the changes discussed above regarding A1 certificates, posting, and work in multiple Member States will not take effect until 24 months after the regulation enters into force. Until then, the current rules remain in effect.
For Belgian employers with cross-border operations, the reform brings both opportunities and new obligations.
On the one hand, the clarifications provide greater legal certainty for international employment. The new exemptions from the application requirement and the potentially longer validity period of certain A1 certificates can also simplify administrative follow-up.
On the other hand, employers must take into account stricter conditions for posting workers, new application requirements, and revised procedures.
HR departments, payroll specialists, and international mobility teams, in particular, would be well advised to evaluate their existing processes in a timely manner and adjust them as necessary.
Contact our experts for tailored advice.
This form can only be sent with the use of technical cookies. You can accept these cookies here.
These cookies are used to distinguish people from bots. Certain data, such as your IP address or language preference, can be sent to Google. More information in our cookie policy.
Lise Bouten
Advisor Social Legal lise.bouten@vdl.be
Evelien Rummens
Manager Social Legal evelien.rummens@vdl.be
Disclaimer
In our opinions, we rely on current legislation, interpretations and legal doctrine. This does not prevent the administration from disputing them or from changing existing interpretations.
Read our latest insights and news releases to stay abreast of changes in your industry.