As a “posted worker”, posted temporarily to another EU country, which country is in charge of my healthcare?

When you are “posted” by your employer, or you “post” yourself as a self-employed person, to work in another EU country (In this case, the 28 EU member states + Iceland, Liechtenstein, Norway and Switzerland), you will remain covered by your home country. If, during your posting, you decide to live permanently in the country where you are posted, you will be covered in the country where you are working using the S1 form.