The National League B is a professional football league in Switzerland, serving as the second tier of the Swiss football league system. It features teams that compete for promotion to the higher Swiss Super League. The league is known for its competitive nature and serves as a platform for clubs to develop talent and gain experience. Founded in 2011, the National League B replaced the previous Challenge League format. The league typically consists of 10 to 12 teams, with each season culminating in playoffs to determine which teams will move up to the top division.