The 2024–25 European Aquatics Euro Cup knockout stage details the matches played to decide the champion of the tournament. Games took place between the 25 January and 24 May 2025.
Qualified teams.
The knockout phase involves 16 teams: the eight teams which qualified as winners and runners-ups of each of the four groups in the group stage, and the eight third and fourth placed teams from the Champions League group stage.
Euro Cup group stage winners and runners-up.
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Eliminated teams from Champions League.
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Draw.
The draw took place in Zagreb on 11 December. The teams were split into two draws, one containing the four teams who finished fourth in the Champions League group stage, who would be pitted up against a Euro Cup group winner. The other half of the draw would see the third place teams from the Champions League group stage be drawn against a runner up of the Euro Cup group stage.
Bracket.
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Eighth-finals.
Matches.
"Radnički Kragujevac won 29–22 on aggregate"
"Jadran Herceg Novi won 18–12 on aggregate"
"HAVK Mladost Zagreb won 31–22 on aggregate"
"Astralpool Sabadell won 26–17 on aggregate"
"A-Híd Vasas Plaket won 25–21 on aggregate"
"AN Brescia won 26–23 on aggregate"
"Recco Waterpolo won 34–10 on aggregate"
"Primorac Kotor won 33–32 on aggregate"
Quarterfinals.
The draw was held on 7 February 2025.
Matches.
"HAVK Mladost Zagreb won 18–17 on aggregate"
"Radnički Kragujevac won 23–19 on aggregate"
"Recco Waterpolo won 25–16 on aggregate"
"Astralpool Sabadell won 26–23 on aggregate"
Semifinals.
Matches.
"Radnički Kragujevac won 25–21 on aggregate"
"Recco Waterpolo won 26–16 on aggregate"
Final.
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Matches.
"Recco Waterpolo won 28–21 on aggregate"