Additions
| from | Name | Pos | Team | Team | ||
|---|---|---|---|---|---|---|
| 07/2016 |  | Alonso | DF |  | Athletic Club U19 | Bilbao U19 |
| 07/2016 | | Daniel Vivian | DF | |||
| 07/2016 | | Mateo | DF | | Athletic Club U19 | Bilbao U19 |
| 07/2016 | | Garai | MF | | Athletic Club U19 | Bilbao U19 |
| 07/2016 | | Iñigo Vicente | FW | | Athletic Club U19 | Bilbao U19 |
| 07/2016 | | Morcillo | FW |  | SCD Durango | Durango |
| 07/2016 | | Xabi Garai | FW | | Athletic Club U19 | Bilbao U19 |
| 07/2016 | | Joseba Etxeberria | MA |  | Athletic Club | Athletic |
Departures
| from | Name | Pos | Team | Team | ||
|---|---|---|---|---|---|---|
| 01/2017 | | Alonso | DF | | SCD Durango | Durango |
| 08/2016 | | Oier Sarriegi | DF |  | SD Leioa | Leioa |
| 07/2016 | | Izaro Abella | MF |  | Athletic Club B | Bilbao B |
| 07/2016 | | Jorge Bengoetxea | MF |  | Club Portugalete | Portugalete |
| 07/2016 | | Markel Lozano | MF |  | SD Zamudio | SD Zamudio |
| 07/2016 | | Íñigo Pradera | FW |  | SD Gernika | Gernika |