FC Seoul U18: every transfer in and out, fees paid and earned, squad market value.
| Date | Player | From | To | Fee |
|---|---|---|---|---|
| 2026-01-16 | Pil-gwan Ko | FC Seoul U18 | FC Seoul | — |
| 2026-01-16 | Jeong-beom Son | FC Seoul U18 | FC Seoul | — |
| 2025-01-17 | Seloh Samuel Gbato | FC Seoul U18 | FC Seoul | — |
| 2025-01-17 | Ki-wook Yun | FC Seoul U18 | FC Seoul | — |
| 2025-01-01 | Yong-hyuk Kim | FC Seoul U18 | Gwangju FC U18 | — |
| 2024-05-31 | Ju-hyeok Kang | FC Seoul U18 | FC Seoul | — |
| 2023-01-01 | Yong-hyuk Kim | FC Seoul U15 | FC Seoul U18 | — |
| 2023-01-01 | Seung-beom Son | FC Seoul U18 | FC Seoul | — |
| 2023-01-01 | Pil-gwan Ko | FC Seoul U15 | FC Seoul U18 | — |
| 2023-01-01 | Jeong-beom Son | FC Seoul U15 | FC Seoul U18 | — |
| 2023-01-01 | Jee-won Kim | FC Seoul U18 | Korea University | — |
| 2022-03-24 | Jae-min Seo | FC Seoul U18 | FC Seoul | — |
| 2022-01-01 | Seong-hun Park | FC Seoul U18 | FC Seoul | — |
| 2022-01-01 | Seloh Samuel Gbato | FC Seoul U15 | FC Seoul U18 | — |
| 2022-01-01 | Ki-wook Yun | FC Seoul U15 | FC Seoul U18 | — |
| 2022-01-01 | Ju-hyeok Kang | FC Seoul U15 | FC Seoul U18 | — |
| 2022-01-01 | Jae-min Ahn | FC Seoul U18 | Dongguk Uni | — |
| 2022-01-01 | Do-yoon Hwang | FC Seoul U18 | Korea University | — |
| 2021-01-07 | Tae-seok Lee | FC Seoul U18 | FC Seoul | — |
| 2021-01-01 | Young-whan Kim | FC Seoul U18 | Incheon Uni. | — |