In the 2020–21 season, Jagiellonia Białystok competed in Ekstraklasa,[2] and the season's Polish Cup edition, as they were eliminated by Górnik Zabrze, following the 1–3 defeat in the round of 64.

[3] Note: Flags indicate national team as defined under FIFA eligibility rules; some limited exceptions apply.

Players may hold more than one non-FIFA nationality.