Can a Ukrainian citizen who entered Poland after February 24, 2022 and has a biometric passport go to another EU country for a few days and then return to Poland?

As of June 11, 2017, according to Regulation (EU) 2017/850 of the European Parliament and of the Council of May 17, 2017, holders of biometric passports issued by the Ukrainian authorities may cross the external border of the European Union without a visa when their total stay does not exceed 90 days during any 180-day period.

Therefore, Ukrainian citizens holding a biometric passport, as visa-free travellers under Regulation (EU) 2016/399 of the European Parliament and of the Council of March 9, 2016 on the EU Code on the rules governing the movement of persons across borders (Schengen Borders Code), are entitled to free movement within the EU for a period of 90 days after entering the EU.

An identical entitlement is provided by the electronic residence permit diia.pl – on its basis, with a valid travel document, one can move within the Schengen area for up to 90 days for each consecutive 180 days.