As the restrictions on movement caused by the COVID-19 are still in place, many cross-border workers have been forced to extend their stay on in the countries they perform work or where they reside in. Meanwhile, performing work in the territory of a specific country affects the tax situation of the employee and may also result in the obligation to pay social security contributions in a country other than before.

This happens, among others in the case of an employee residing in Poland and performing work in another country on the basis of a contract with a foreign employer. If he provides work remotely from his place of residence, the remuneration for such work is taxable in Poland. The obligation to pay monthly tax advances then lies with the employee himself and not the employer. On the other hand, an employer based in a country applying EU regulations on the coordination of social security systems should take into account the risk that an employee will be considered a person subject to Polish social security regulations and for the period of work in Poland ZUS will expect contributions paid to the Polish system.

The authors of the article discuss the effects of personal income tax and social security resulting from several, the most typical scenarios of prolonged stay of a cross-border employee in one country and perform work on its territory.