Posting Workers vs. Multi State Workers
InternationalSocial Security law is governed under the principle of territoriality, which states that, in general, workers are subjected to the law of the country in which they are physically working. As a result, they will also contribute into the Social Security system of that country.
In this post we will talk about two important exceptions to this general rule of territoriality regulated at a European Union level:
1 - Posting of workers
Posting of workers is a scenario in which a worker is posted from an EU country member, where he is based and have an employment relationship, to another one for a specific purpose/mission and for a limited period of time.
In this first scenario, EU Social Security legislation allows them to maintain their ties to the Social Security of their country of origin for the time they are posted(granting them with the well-known A1 form).
2 - Multi-State Worker
In this second scenario, we refer to a situation in which the employee is working simultaneously in two or more Member States. In this case, as long as they carry out a substantial part* of their activity in their country of residence, they will be tied to the social security system of that country.
*A “substantial part” of their activity is considered to be when the employee spends at least 25% of their working time in that country.
