The 2025 Copa Sudamericana group stage was played from 1 April to 29 May 2025. A total of 32 teams competed in the group stage to decide 16 of the 24 places in the final stages of the 2025 Copa Sudamericana.
<section begin=Draw /> The draw for the group stage was held on 17 March 2025, 20:00 PYT (), at the CONMEBOL Convention Centre in Luque, Paraguay.
Teams were seeded by their CONMEBOL Clubs ranking as of 16 December 2024 (shown in parentheses), taking into account the following three factors:
For the group stage, the 32 teams were drawn into eight groups (Groups AâÂÂH) of four containing a team from each of the four pots. The four losers of the Copa Libertadores third stage were seeded into Pot 4. Teams from the same association could not be drawn into the same group.
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The following are the four losers of the third stage of the 2025 Copa Libertadores qualifying stages which joined the 12 direct entrants and the 16 Copa Sudamericana first stage winners in the group stage.
<section begin=Format /> In the group stage, each group was played on a home-and-away round-robin basis. Teams were ranked according to the following criteria: 1. Points (3 points for a win, 1 point for a draw, and 0 points for a loss); 2. Goal difference; 3. Goals scored; 4. Away goals scored; 5. CONMEBOL ranking (Regulations Article 2.4.2).
The winners of each group advanced to the round of 16 of the final stages, whilst the runners-up of each group advanced to the knockout round play-offs of the final stages.<section end=Format />
The schedule of each matchday was as follows (Regulations Article 2.2.2).