The finals open on 11 June with games including Slovakia vs Spain and Portugal vs France.
Czechia and Finland made the most of first-leg leads while Georgia beat Croatia after an epic shoot-out to decide an equally dramatic tie.
Raising football stars in the under-21 category will present themselves in eight Slovak stadiums, i.e. in Bratislava, Trnava, Nitra, Dunajská streda, Trenčín, Žilina, Košice, and Prešov.
The nine group winners and three best runners-up have booked spots alongside hosts Slovakia in next summer's finals.
The groups run until October 2024 with 12 direct finals slots and six play-off berths.
Slovakia will stage the 2025 UEFA European Under-21 Championship.
