Olympiacos (Super League Greece): every transfer in and out, fees paid and earned, squad market value, €140m spent and €81m earned.
| Date | Player | From | To | Fee |
|---|---|---|---|---|
| 2026-08-08 | Georgios Masouras | Olympiacos | Neom Sports Club | Free |
| 2026-08-06 | Gabriel Strefezza | Olympiacos | Palermo FC | €4m |
| 2026-08-06 | Francisco Ortega | Olympiacos | Club Atlético River Plate | €5m |
| 2026-08-05 | Konstantinos Tzolakis | Olympiacos | Hull City | €23m |
| 2026-07-30 | Antonis Papakanellos | Olympiacos | A.G.S Asteras Tripolis | Loan |
| 2026-07-30 | Gustavo Sá | Nottingham Forest | Olympiacos | Loan |
| 2026-07-29 | Stefan Ortega | Nottingham Forest | Olympiacos | Free |
| 2026-07-24 | Manolis Saliakas | FC St. Pauli | Olympiacos | €1.3m |
| 2026-07-23 | Jefté Betancor | Olympiacos | UD Las Palmas | Free |
| 2026-07-18 | Joel Roca | Girona FC | Olympiacos | €5m |
| 2026-07-15 | Diogo Nascimento | Olympiacos | Rio Ave FC | Loan |
| 2026-07-09 | Jota Silva | Nottingham Forest | Olympiacos | Loan |
| 2026-07-06 | Zinedin Smajlović | Sandefjord Fotball | Olympiacos | €5m |
| 2026-07-03 | Balsa Popovic | Crvena Zvezda | Olympiacos | €1.5m |
| 2026-07-02 | Balsa Popovic | Crvena Zvezda | Olympiacos | Free |
| 2026-07-01 | Nikolaos Botis | Olympiacos | Pogon Szczecin | Free |
| 2026-07-01 | Player | Iraklis Thessaloniki | Olympiacos | Free |
| 2026-07-01 | Doron Leidner | Olympiacos | Hapoel Tel Aviv | €350k |
| 2026-07-01 | Rúben Vezo | Olympiacos | TBC | Free |
| 2026-07-01 | David Carmo | Nottingham Forest | Olympiacos | €9m |