The 1. Liga ragby XV is the second level of domestic club rugby union in the Czech Republic, below the first division, the Extraliga ragby XV. There is also one club from Slovakia in the league.
The season runs from mid-September to the end of May.
The league started out as the Druhá Liga (Second League), but was renamed the PrvnàLiga (First League) in the 1999-2000 season. For sponsorship reasons it has been called KB PrvnàLiga until the 2015/16 season.
2024 season