The 2025 K League 1, also known as the Hana Bank K League 1 for sponsorship reasons, is the ongoing 43rd season of the top division of professional football in South Korea, and the twelfth season of the K League 1. Ulsan HD are the three-time defending champions.
Rule changes.
The following rules were newly introduced for the 2025 season.
Teams.
Team changes.
FC Anyang were promoted from the K League 2 for the first time in the club's history. Incheon United were relegated to the K League 2, absenting from the top flight of South Korean football for the first time in the club's history.
Locations.
The following twelve clubs are competing in the 2025 K League 1.
Foreign players.
Each team may have up to six foreign players registered, but may only field up to five at any given time. As a military-owned team, Gimcheon Sangmu are not allowed to sign any foreign players.
A North Korean player is considered to be a domestic player under South Korean nationality law. As of 2025, K League has a homegrown system under which players of foreign nationality who have grown up in Korea are considered to be domestic players when registering as new players.
Players in bold were registered during the mid-season transfer window.
Results.
Matches 1–22.
Teams played each other twice, once at home, once away.
Matches 23–33.
Teams played each other once, either at home or away.
Matches 34–38.
Teams played each other once, either at home or away.
Relegation play-offs.
The tenth-placed team and the eleventh-placed team will play against the play-off winners and the runners-up of the K League 2, respectively, in the relegation play-offs.
Attendance.
Attendants who entered with free ticket are not counted.