Published: 04 November 2026
27 October 2026 saw publication in the Official Journal of the European Union of Regulation (EU) 2026/2359, amending regulations (EC) 883/2004 and 987/2009 concerning the coordination of social security systems.
The amendments concern, in particular, seconded workers and those who routinely carry out their activities in multiple Member States. While confirming the general principles already provided for by European legislation, this Regulation specifies the conditions for the maintenance or identification of the applicable social security legislation and introduces further provisions.
Workers seconded to another Member State
Concerning secondment, the principle detailed in Article 12 of Regulation (EC) 883/2004 remains unchanged, according to which workers temporarily seconded to another Member State, and self-employed workers who temporarily carry out their activity there, may continue to be subject to the social security legislation of their State of origin, provided that the expected duration of the activity does not exceed 24 months and that the worker is not replacing another seconded employee or self-employed worker. Workers may however be replaced if they have interrupted their service prematurely, provided that the total period of activity carried out in the host State by the person replacing them does not exceed 24 months.
Certain requirements for application of this regulation are also specified:
- employees hired with a view to being sent abroad must have been subject, for at least three months immediately prior to their hiring, to the legislation of the Member State in which the employer is established;
- self-employed workers must have carried out their activity in their State of origin for at least three months and the requirements for resumption of the same on their return must be maintained.
After a total of 24 months’ activity by the same person in the host State, even with interruptions not exceeding two months, the social security secondment rules for that State can no longer be used again until at least two months have elapsed since the end of the previous activity, except for specific exceptions.
From a procedural point of view, the employer or the self-employed worker must inform the competent institution of the State whose legislation is applicable before the start of activity abroad and request that the relevant certificate be issued (normally, the Portable Document A1).
Prior communication and a request for the certificate to be issued are not necessary for “business trips“, i.e. temporary activities such as meetings, conferences, or training that do not involve the provision of services or the supply of goods. The same exemption also covers activities lasting no longer than three consecutive days of work over thirty consecutive days, with the exception of those in the building sector expressly identified in the Regulations.
Employers remain responsible for providing the workers concerned with documentation attesting to the request for issue of an A1 certificate or to the existence of an exemption.
The new Regulation also strengthens checks on the validity of certificates and the exchange of information between institutions, detailing specific deadlines for the verification, rectification or revocation of documents and strengthening the tools for cooperation and combating errors, fraud, and abuse.
Workers working in multiple Member States
For workers who routinely work in two or more Member States, Article 13 of Regulation (EC) 883/2004 stipulates that, in general, the applicable social security legislation is that of their State of residence, provided that the person in question performs a substantial part of their activity in the same State. If this condition is not met, in the case of a worker employed by a single employer, the legislation of the State in which the latter has its registered office or its domicile applies, without prejudice to the specific rules provided for in other cases.
The changes introduced by the new Regulation confirm these principles and clarify two important points regarding methods of application. Firstly, in order to identify the employer’s registered office or domicile, it is necessary to consider not only the formal elements, but above all the place where essential company decisions are made and central administration functions carried out, after an overall assessment of the relevant circumstances.
Secondly, determination of the applicable social security legislation is expected to have a maximum validity of 24 months, after which a new examination will be needed to verify which legislation should be applied.
Effective date and transitional regime
The Regulation comes into force on 1 November 2026. The new provisions concerning secondment of workers and carrying out of activities in two or more Member States will instead apply from 2 November 2028.
Secondments started before that date shall continue to be subject to the previous regulation (Article 12 of Regulation 883/2004).
If the new provisions involve a change in the applicable social security legislation for workers who carry out activities in two or more Member States, these shall instead be able to maintain the previous one, provided that the situation remains unchanged until 2 November 2036. The worker in question retains, however, the right to request the application of the new provisions.
Toffoletto De Luca Tamajo is at your disposal should you need any further clarification and/or details.