Kocaelispor U19: every transfer in and out, fees paid and earned, squad market value.
| Date | Player | From | To | Fee |
|---|---|---|---|---|
| 2026-03-03 | Arda Özyar | Kocaelispor U19 | Kocaelispor | — |
| 2026-02-22 | Deniz Ceylan | Kocaelispor U19 | Kocaelispor | — |
| 2025-08-08 | Deniz Ceylan | Galatasaray U17 | Kocaelispor U19 | Free |
| 2025-08-08 | Arda Özyar | Samsunspor U19 | Kocaelispor U19 | Free |
| 2020-12-18 | Furkan Gedik | Kocaelispor U19 | Kocaelispor | — |
| 2020-08-04 | Doğukan Kaya | Kocaeli U19 | Kocaelispor | — |
| 2019-07-01 | Furkan Gedik | Kocaelispor Yth | Kocaelispor U19 | — |
| 2017-07-01 | Doğukan Kaya | Kocaelispor Yth | Kocaeli U19 | — |