| 30 Aug 19 | Juan Castillo |  ChelseaCHE | → |  Ajax AmsterdamAJA | Loan |
| 30 Aug 19 | Juan Castillo | ChelseaCHE | → | Ajax AmsterdamAJA | Loan |
| 09 Aug 19 | L. Schöne Lasse Schöne | Ajax AmsterdamAJA | → |  GenoaGEN | Undisclosed |
| 09 Aug 19 | L. Schöne Lasse Schöne | Ajax AmsterdamAJA | → | GenoaGEN | Undisclosed |
| 30 Jul 19 | Alex Mendez |  SC FreiburgFREI | → | Ajax AmsterdamAJA | Undisclosed |
| 30 Jul 19 | Alex Mendez | SC FreiburgFREI | → | Ajax AmsterdamAJA | Undisclosed |
| 18 Jul 19 | M. de Ligt Matthijs de Ligt | Ajax AmsterdamAJA | → |  JuventusJUV | 75000000 |
| 18 Jul 19 | M. de Ligt Matthijs de Ligt | Ajax AmsterdamAJA | → | JuventusJUV | 75000000 |
| 01 Jul 19 | D. Sinkgraven Daley Sinkgraven | Ajax AmsterdamAJA | → |  Bayer LeverkusenLEV | Undisclosed |
| 01 Jul 19 | F. de Jong Frenkie de Jong | Ajax AmsterdamAJA | → |  BarcelonaBAR | 75000000 |
| 01 Jul 19 | F. de Jong Frenkie de Jong | Ajax AmsterdamAJA | → | BarcelonaBAR | 75000000 |
| 01 Jul 19 | D. Sinkgraven Daley Sinkgraven | Ajax AmsterdamAJA | → | Bayer LeverkusenLEV | Undisclosed |
| 04 Apr 19 | R. Marin Razvan Marin |  Standard LiegeSTL | → | Ajax AmsterdamAJA | 12,500,000 |
| 16 Jan 19 | Max Wober | Ajax AmsterdamAJA | → |  SevillaSEV | Loan |
| 16 Jan 19 | Max Wober | Ajax AmsterdamAJA | → | SevillaSEV | Loan |
| 01 Jan 19 | L. Magallán Lisandro Magallán |  Boca JuniorsCABJ | → | Ajax AmsterdamAJA | Undisclosed |
| 01 Jan 19 | L. Magallán Lisandro Magallán | Boca JuniorsCABJ | → | Ajax AmsterdamAJA | Undisclosed |