From Bulbapedia, the community-driven Pokémon encyclopedia.
The Kalos League (Japanese: カロスリーグ Kalos League) is the regional Pokémon League of the Kalos region. The Kalos League is composed of eight Kalos Gym Leaders and four Kalos Elite Four members, along with the Champion. Pokémon Trainers who earn eight Gym Badges by defeating the Gym Leaders of the Kalos League qualify to challenge the Elite Four located in the Pokémon League building.
In the anime, Trainers who collect eight Badges can enter the Kalos League championship competition, known as the Lumiose Conference.