Boro U18: every transfer in and out, fees paid and earned, squad market value.
| Date | Player | From | To | Fee |
|---|---|---|---|---|
| 2018-07-01 | Zach Hemming | Boro U18 | Boro U23 | — |
| 2018-07-01 | Nathan Wood | Boro U18 | Boro U23 | — |
| 2018-07-01 | Billal Brahimi | Boro U18 | Boro U23 | — |
| 2017-07-01 | Nathan Wood | Boro Yth. | Boro U18 | — |
| 2017-07-01 | Billal Brahimi | Leixões U17 | Boro U18 | — |
| 2016-07-01 | Zach Hemming | Boro Yth. | Boro U18 | — |
| 2016-07-01 | Marcus Tavernier | Boro U18 | Boro U23 | — |
| 2014-07-01 | Nathan McGinley | Boro U18 | Boro U21 | — |
| 2013-07-01 | Brad Halliday | Boro U18 | Boro U21 | — |