The 2018–19 season was Jagiellonia Białystok's 12th consecutive season in the Ekstraklasa and 98th year in existence as a football club.

In addition to the domestic league, Jagiellonia Białystok participated in this season's editions of the Polish Cup and the UEFA Europa League.

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

Players may hold more than one non-FIFA nationality.

Source: Competitions Source: Competitions