The I-League 3 acts as the qualifiers for the I-League 2, comprising 25 clubs nominated by member associations based on their performances in the state leagues.
The 25 teams are divided into five groups of five each. Each group is played in a centralised venue (Naihati, Goa, Aizawl, Diphu and Srinagar) in a single round-robin format. The group winners and runners-up qualify for the Play-offs.
The Play-offs for the 2024-25 season were held in Kalyani and Naihati in West Bengal, with 10 teams divided into two groups of five with matches played in a single round-robin format. The group winners (Diamond Harbour FC and Chanmari FC) and runners-up (KLASA FC and SAT Tirur) qualified for the 2024-25 I-League 2. The third-placed teams (Karbi Anglong Morning Star FC and MYJ-GMSC) qualified for the 2025-26 I-League 2. Diamond Harbour defeated Chanmari 1-0 to win the 2024-25 I-League 3 trophy.