| Challenger Heilbronn | 05/08 14:50 | 14 | Alexey Vatutin v Haerteis, Johannes | 3-6,4-6 | |
| Challenger Mauthausen | 05/01 11:45 | 14 | Lucas Miedler v Haerteis, Johannes | 7-6,6-2 | |
| ITF - M25 Santa Margherita | 04/27 12:00 | 26 | Haerteis, Johannes v Gianmarco Ferrari | 5-7,1-6 | |
| ITF - M25 Santa Margherita | 04/26 15:10 | 25 | Haerteis, Johannes v Felix Mischker | 5-7,6-3,6-1 | |
| Challenger - Oeiras | 04/04 09:30 | 19 | Ergi Kirkin v Haerteis, Johannes | 6-3,6-2 | |
| Challenger Oeiras Qual | 04/03 09:00 | 14 | Arjun Kadhe v Haerteis, Johannes | 6-3,5-7,1-6 | |
| Marbella, Spain | 03/28 08:00 | 19 | Alexander Shevchenko v Haerteis, Johannes | 6-3,6-2 | |
| Marbella, Spain | 03/27 09:00 | 14 | Haerteis, Johannes v Elliot Benchetrit | 7-5,6-2 | |
| Challenger Biel | 03/20 12:35 | 14 | Haerteis, Johannes v Pervolarakis, Michail | 3-6,2-6 | |
| ITF - M25 Trimbach | 03/19 13:50 | 28 | Leandro Riedi v Haerteis, Johannes | 6-4,6-4 | |
| ITF - M25 Trimbach | 03/18 12:15 | 27 | Otto Virtanen v Haerteis, Johannes | 4-6,6-4,4-6 | |
| ITF - M25 Trimbach | 03/17 09:00 | 26 | Haerteis, Johannes v Frantzen, Constantin | 6-3,6-7,6-2 | |
| ITF - M25 Trimbach | 03/16 09:00 | 25 | Gabriele Moghini v Haerteis, Johannes | 5-7,4-6 | |
| ITF - M15 Villena | 02/05 09:30 | 28 | [310] Nikolas S Izquierdo v Haerteis, Johannes [423] | 6-3,4-6,6-2 | |
| ITF - M15 Villena | 02/04 12:10 | 27 | Haerteis, Johannes v Thomas Deschamps | 6-4,7-6 | |
| ITF - M15 Villena | 02/03 11:15 | 26 | Haerteis, Johannes v Alejandro Manzanera Pertusa | 3-6,6-0,6-2 | |
| ITF - M15 Villena | 02/02 13:50 | 25 | Haerteis, Johannes v Dali Blanch | 2-6,6-3,6-4 | |
| ITF M25 Manacor | 01/15 10:00 | 28 | [384] Alberto Barroso Campos v Haerteis, Johannes [441] | 7-6,6-4 | |
| ITF M25 Manacor | 01/14 11:00 | 27 | [421] Peter Heller v Haerteis, Johannes [441] | 6-7,6-4,3-6 | |
| ITF M25 Manacor | 01/13 11:30 | 26 | Rikl, Patrik v Haerteis, Johannes | Walkover | |
| ITF M25 Manacor | 01/12 10:00 | 25 | Sandro Cottino v Haerteis, Johannes | 6-4,3-6,4-6 | |
| Challenger Manama | 11/24 08:00 | 26 | [302] Evgeny Karlovskiy v Haerteis, Johannes [463] | 6-3,6-1 | |
| Challenger Manama | 11/23 11:40 | 25 | [463] Haerteis, Johannes v Erler, Alexander [339] | 6-3,6-4 | |
| Challenger Manama | 11/22 08:00 | 19 | [463] Haerteis, Johannes v Lazarov, Alexandar [462] | 3-6,6-7 | |
| Challenger Manama | 11/21 10:05 | 14 | Haerteis, Johannes v Alhogbani, Ammar | 6-2,6-1 | |
| Helsinki, Finland | 11/14 09:00 | 26 | [430] Haerteis, Johannes v Viktor Durasovic [354] | 4-6,6-7 | |
| Challenger Eckental | 11/02 18:15 | 25 | [133] Maxime Cressy v Haerteis, Johannes [407] | 6-7,6-4,6-3 | |
| Challenger Eckental | 11/01 11:15 | 19 | [407] Haerteis, Johannes v Ignatik, Uladzimir [404] | 4-6,6-2,7-6 | |
| Challenger Eckental | 10/31 13:30 | 14 | [315] Lucas Miedler v Haerteis, Johannes [427] | 3-6,7-5,3-6 | |
| Challenger Ismaning | 10/25 11:50 | - | [377] Otto Virtanen v Haerteis, Johannes [427] | 4-6,6-3,6-3 |