The National Super League 4-Day Tournament is a domestic first-class cricket competition, which is held annually in Sri Lanka. Five cricket teams representing five districts of the country take part in the tournament. The league is organized by the Sri Lanka Cricket (SLC) beginning in the 2022 season. In January 2022, the SLC launched the tournament. The squads for the competition are announced based on the performances in the Major League Tournament, with 26 clubs clustered under five teams. The tournament serves as the criteria to select players for Sri Lanka's Test squad. The tournament runs alongside the National Super League Limited Over Tournament.