- J. Amann
FSV Mainz 05Free agent—30 Jun 2026 
Niklas Swider
Borussia MönchengladbachLoan—30 Jun 2026
N. Jahn
VfL BochumTransfer—30 Jun 2026- J. AmannFSV Mainz 05Free agent—30 Jun 2026
- Raphael Ott
FC Schalke 04Return from loan—29 Jun 2026 - J. SachseFC Schalke 04Loan—1 Feb 2026
- J. Vega Zambrano
SC Paderborn 07Transfer—4 Jan 2026 
J. Agyekum
Hamburger SVLoan—1 Sept 2025- M. Sponsel
1. FC KölnFree agent—30 Jun 2025 - V. CarusFC Schalke 04Free agent—30 Jun 2025
- L. Münst
VfB StuttgartFree agent—30 Jun 2025 
A. SchulzSC Paderborn 07Free agent—30 Jun 2025- M. PledlSC Paderborn 07Free agent—30 Jun 2025
- Paul Friedrich PöpperlFC Schalke 04Loan—3 Jan 2025
- M. El Mala1. FC KölnLoan—2 Jul 2024
S. El Mala1. FC KölnLoan—2 Jul 2024
Dudu
Werder BremenFree—1 Jul 2024- T. Anselm
Lask LinzLoan—18 Jan 2024
L. Dietz
Patro EisdenFree agent—30 Jun 2026- J. AgyekumHamburger SVReturn from loan—29 Jun 2026
- J. SachseFC Schalke 04Return from loan—29 Jun 2026
- Dudu
EstrelaTransfer—1 Feb 2026 - Raphael OttFC Schalke 04Loan—1 Feb 2026
Jonah Benedict StickerSC Paderborn 07Transfer—1 Sept 2025- S. El Mala1. FC KölnBack from Loan—1 Jul 2025
Zoumana Keita
AnderlechtTransfer—1 Jul 2025
S. Lopes CabralEstrelaFree Transfer—1 Jul 2025- Paul Friedrich PöpperlFC Schalke 04Back from Loan—1 Jul 2025
E. Lofolomo
Zulte WaregemFree Transfer—1 Jul 2025- M. El Mala1. FC KölnBack from Loan—1 Jul 2025
Z. KeitaAnderlechtTransfer—30 Jun 2025- M. El Mala1. FC Köln450K—1 Jul 2024
B. Voll
FC St. Pauli——1 Jul 2024- S. El Mala1. FC Köln450K—1 Jul 2024