New EU Social Security Rules 2026: What Changes for Companies with Workers in Multiple Countries

Key data

If you have posted workers, employees who regularly operate in multiple countries, or self-employed professionals providing services in different Member States, this reform directly affects you. Regulation (EU) 2026/2359, published on 27 October 2026, amends the legal framework that has been regulating which country collects social contributions when a worker crosses borders within Europe for over twenty years.

The change is significant: it affects the determination of applicable national legislation, that is, the fundamental question of "in which country should this worker contribute?" An incorrect answer can result in double contributions, penalties, or claims from the Social Security institutions of the countries involved.

What does this regulation establish?

Regulation (EU) 2026/2359 amends two regulations that are the cornerstone of Social Security coordination in Europe:

• Regulation (EC) No 883/2004: establishes the general principles of coordination between national Social Security systems. It defines, among other things, which national legislation applies to each worker based on their employment and geographical situation.
• Regulation (EC) No 987/2009: develops the practical application rules of the above, including administrative procedures between institutions in different countries and the forms used (such as Form A1).

The amendments introduced by the new regulation specifically affect:

The territorial scope of application covers all EU Member States, plus the countries of the European Economic Area (Norway, Iceland, and Liechtenstein) and Switzerland, which also apply these regulations through bilateral agreements.

Economic and operational impact

The economic impact of this reform does not come from a fixed rate or amount: it comes from the risk of contributing in the wrong country or not having documentation in order. The practical consequences for companies are:

• Review of active affiliations: if the new criteria for applicable legislation change the country of contribution for any worker, the company must process the deregistration in one system and registration in another, with the associated administrative and management costs.
• Update of Form A1: the A1 certificate certifies in which country a posted worker contributes. If the procedures for issuing it change, existing A1 certificates may need review or renewal.
• Risk of double contribution: without correct application of the new rules, a company may end up contributing simultaneously in two countries for the same worker, doubling the cost.
• Coordination with foreign institutions: the procedures between Social Security bodies in different countries are also modified, which may affect resolution times and required documentation.

Who does it affect?

• Companies with posted workers: any company that sends employees to work temporarily in another EU, EEA, or Swiss country.
• Companies with multinational workforces: business groups with employees who regularly work in multiple European countries simultaneously.
• Cross-border workers: people who reside in one country and work in another on a regular basis (for example, residing in Spain and working in France).
• International self-employed professionals: self-employed professionals who provide services in more than one EU, EEA, or Swiss Member State.
• HR and payroll departments: those responsible for managing affiliation and contribution of employees in international mobility.
• Labor advisors and management firms: professionals who manage posting documentation and Form A1 for their clients.

Practical example

A Spanish technology company has three engineers posted in Germany for 18 months on a client project. Currently, these workers contribute in Spain thanks to the Form A1 that certifies their temporary posting.

With the entry into force of Regulation (EU) 2026/2359, the company must verify that the new criteria for determining applicable legislation do not alter the situation of these workers. If the new criteria modify the thresholds or conditions of posting, it may be necessary to:

• Request new A1 certificates adapted to the updated procedures.
• Review whether the duration or conditions of posting still fit within Spanish legislation as applicable.
• Coordinate with the German Social Security institution if there is any change in applicable legislation.

The same scenario applies to a Spanish self-employed professional who invoices services to clients in Spain, France, and Portugal: they must review under which national legislation they contribute and whether the new regulation criteria alter that determination.

What should companies do now?

1. Identify all workers in international mobility: create an inventory of posted workers, cross-border workers, or those who regularly work in multiple EU, EEA, or Swiss countries.
2. Review existing Form A1 certificates: check the validity and conditions of active A1 certificates. Adjustments in procedures may require renewals or updates.
3. Consult with a specialist advisor in international mobility: changes in applicable legislation criteria require case-by-case analysis. An error in determination can result in double contributions or claims from foreign institutions.
4. Update internal HR procedures: payroll and HR departments must understand the new criteria and administrative procedures to correctly manage registrations, deregistrations, and certifications.
5. Coordinate with the Social Security institutions involved: if there are workers whose applicable legislation may be affected, initiate contact as soon as possible with the competent institutions of the countries involved.
6. Monitor the entry into force date: the regulation does not specify a concrete application date. It is essential to monitor the publication of supplementary provisions that set adaptation timelines.

Official source

Consult the complete regulation at official source

Disclaimer: This article is for informational purposes only and does not constitute legal advice. For specific decisions, consult a qualified professional. Source: https://eur-lex.europa.eu/./legal-content/AUTO/?uri=OJ:L_202602359