Round: 25 Ground: Carpet indoor
| ITF Germany F4 | 2016/06/22 14:00 | Onken, Julian v Krawietz, Kevin | 3-6,3-6 |
| ITF Germany F4 | 2016/06/19 09:00 | Onken, Julian v Peters, Flemming | 3-6,6-4,6-4 |
| ITF Poland F2 | 2016/06/02 09:30 | Pawel Juszczak v Onken, Julian | 6-4,6-2 |
| ITF Poland F2 | 2016/06/01 08:40 | Zbroja, Piotr v Onken, Julian | 3-6,6-7 |
| Italie F8, Qualifications Simples | 2016/04/27 11:50 | Daniel Altmaier v Onken, Julian | 6-2,6-3 |
| Italie F8, Qualifications Simples | 2016/04/25 08:00 | Onken, Julian v Toby Martin | 6-3,6-2 |
| ITF Italy F8 Qual | 2016/04/23 07:30 | Onken, Julian v Palmese, Andrea | 6-2,6-2 |
| ITF Italy F7 | 2016/04/20 10:00 | Enzo Couacaud v Onken, Julian | 6-3,4-6,6-1 |
| ITF Croatia F2 | 2016/03/05 10:30 | Borroni, Andrea v Mrazek, David | 6-4,7-6 |
| ITF Croatia F1 | 2016/02/27 10:30 | de Rosa, Marco v Mrazek, David | 0-6,0-6 |