K4 League (South Korea) 2026/27

The K4 League operates as the fourth tier of the South Korean football pyramid, sitting below the professional K League 1 and K League 2, and the semi-professional K3 League. It serves as the highest amateur and semi-professional division in the country, positioned directly above the amateur K5 League. The competition was established in 2020 by the Korea Football Association (KFA) following a structural reorganisation that renamed the previous K3 League Basic to create a formal semi-professional tier. The season format involves a double round-robin structure where each team plays 24 matches. There is no playoff phase for determining the league title; the team accumulating the most points is crowned champion. This straightforward system distinguishes the competition from leagues that utilise knockout stages for their primary title. Promotion and relegation links exist primarily with the K3 League. The K4 champion is automatically promoted to the K3 League. Additionally, a promotion/relegation playoff determines the second spot: the K4 runner-up plays against the 15th-placed team from the K3 League. Relegation from the K4 to the K5 is not yet fully implemented but is planned for future seasons. The league allows reserve teams from K League clubs, such as Jeonbuk Hyundai Motors B, to participate. Notable reforms in 2025 included the removal of the Asian player quota, allowing four foreign players of any nationality, and increasing squad sizes from 18 to 20. The K4 League is distinguished from the K3 League by its lower competitive tier and from the K5 League by its semi-professional status, where players may receive stipends, unlike the strictly amateur K5. The league is managed under the K League umbrella, with official information hosted on kleague.com.