Additions
| from | Name | Pos | Team | Team | ||
|---|---|---|---|---|---|---|
| 07/2011 |  | Kepa | GK |  | Athletic Club | Athletic |
| 07/2011 | | Urtzi | GK | |||
| 07/2011 | | Eneko Zabaleta | DF |  | Athletic Club U19 | Bilbao U19 |
| 07/2011 | | Aymeric Laporte | DF |  | Athletic Club U17 | U17 |
| 07/2011 | | Mikel | DF | | Athletic Club U19 | Bilbao U19 |
| 07/2011 | | Aketxe | MF | |||
| 07/2011 | | Iker Guarrotxena | MF | |||
| 07/2011 | | Jon Iru | MF | |||
| 07/2011 | | Magdaleno | MF |  | Zalla UC | Zalla UC |
| 07/2011 | | Salinas | MF | |||
| 07/2011 | | Sabin | FW | |||
| 07/2011 | | Sergio Mendigutxia | FW | | Athletic Club U19 | Bilbao U19 |
Departures
| from | Name | Pos | Team | Team | ||
|---|---|---|---|---|---|---|
| 01/2012 | | Sabin | FW |  | Athletic Club B | Bilbao B |
| 07/2011 | | Gorka Magunazelaia | GK |  | Sestao River | Sestao River |
| 07/2011 | | Álvaro Hernando | DF |  | UD Logroñés | UD Logroñés |
| 07/2011 | | Bustinza | DF | | Athletic Club B | Bilbao B |
| 07/2011 | | Jon García | DF | | Athletic Club B | Bilbao B |
| 07/2011 | | Rocha | DF | | UD Logroñés | UD Logroñés |
| 07/2011 | | Álvaro Peña | MF | | Athletic Club | Athletic |
| 07/2011 | | Dani Suárez | MF |  | SD Lemona | SD Lemona |
| 07/2011 | | Domínguez | MF |  | SD Oyonesa | SD Oyonesa |
| 07/2011 | | Iñigo Eguaras | MF | | Athletic Club B | Bilbao B |
| 07/2011 | | Eraña | MF | | Athletic Club B | Bilbao B |
| 07/2011 | | Jonxa | MF | | Athletic Club B | Bilbao B |
| 07/2011 | | Ruiz de Galarreta | MF | | Athletic Club B | Bilbao B |
| 07/2011 | | Vilarchao | MF | | Sestao River | Sestao River |
| 07/2011 | | Yurrebaso | FW | | Athletic Club B | Bilbao B |