Olympiakos Syndesmos Filathlon Peiraios (Super League 1): every transfer in and out, fees paid and earned, squad market value, €145m spent and €196m earned.
| Date | Player | From | To | Fee |
|---|---|---|---|---|
| 2026-07-01 | Nikolaos Botis | Olympiacos | Without Club | — |
| 2026-02-06 | Nikolaos Athanasiou | Olympiacos | OFI Crete | Loan |
| 2026-02-06 | Stavros Pnevmonidis | Olympiacos | Atromitos | Loan |
| 2026-02-03 | Clayton | Rio Ave | Olympiacos | €5m |
| 2026-02-02 | Gabriel Strefezza | Olympiacos | Parma | Loan |
| 2026-02-02 | Gustavo Mancha | Olympiacos | Rio Ave | Loan |
| 2026-02-02 | Roman Yaremchuk | Olympiacos | Lyon | Loan |
| 2026-01-29 | André Luiz | Rio Ave | Olympiacos | €6.8m |
| 2026-01-26 | Pep Biel | Olympiacos | Charlotte | €3.5m |
| 2026-01-01 | Rémy Cabella | Olympiacos | FC Nantes | Loan |
| 2025-09-01 | Daniel Podence | Al-Shabab | Olympiacos | Loan |
| 2025-09-01 | Gustavo Mancha | Fortaleza | Olympiacos | €4.5m |
| 2025-08-31 | Mehdi Taremi | Inter | Olympiacos | €2m |
| 2025-08-22 | Alexandros Anagnostopoulos | Olympiacos | AE Larisa | Free |
| 2025-08-13 | Georgios Masouras | Olympiacos | Al-Khaleej | Loan |
| 2025-08-13 | Kristoffer Velde | Olympiacos | Portland | €4.3m |
| 2025-08-08 | Jefté Betancor | Olympiacos | Albacete | Loan |
| 2025-07-31 | Gabriel Strefezza | Como | Olympiacos | €8m |
| 2025-07-22 | Konstantinos Kostoulas | Olympiacos | OFI Crete | Free |
| 2025-07-13 | Diogo Nascimento | Vizela | Olympiacos | €4m |