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