| Challenger de Acapulco | 04/16 01:45 | 25 | [305] Sebastian Fanselow v Alexis Galarneau [170] | 3-6,2-6 | |
| Challenger de Morelos | 04/08 22:40 | 25 | [306] Sebastian Fanselow v Maxime Cressy [193] | 3-6,3-6 | |
| ITF M25 Trnava | 03/31 09:00 | 29 | [397] Jakub Nicod v Sebastian Fanselow [319] | 6-3,6-1 | |
| ITF M25 Trnava | 03/30 11:50 | 28 | [471] Max Hans Rehberg v Sebastian Fanselow [319] | 5-7,6-4,4-6 | |
| ITF M25 Trnava | 03/29 11:00 | 27 | [492] Martyn Pawelski v Sebastian Fanselow [319] | 7-6,6-7,4-6 | |
| ITF M25 Trnava | 03/28 12:00 | 26 | Aleksandr Braynin v Sebastian Fanselow | 4-6,7-6,4-6 | |
| ITF M25 Trnava | 03/26 15:00 | 25 | [428] David Poljak v Sebastian Fanselow [319] | 3-6,2-6 | |
| ITF M25 Loulé | 03/22 10:30 | 27 | Adria Soriano Barrera v Sebastian Fanselow | 7-6,0-6,7-6 | |
| ITF M25 Loulé | 03/21 10:30 | 26 | Tomas C Abasolo v Sebastian Fanselow | 1-6,1-6 | |
| ITF M25 Loulé | 03/20 15:00 | 25 | Federico Iannaccone v Sebastian Fanselow | 3-6,2-6 | |
| Challenger de Hamburgo | 03/12 12:30 | 25 | [175] Yunchaokete Bu v Sebastian Fanselow [316] | 6-1,6-3 | |
| ITF M25 Quinta Do Lago | 03/06 12:15 | 25 | [389] George Loffhagen v Sebastian Fanselow [316] | 6-4,6-4 | |
| Challenger de Nueva Delhi | 02/25 07:20 | 14 | Sebastian Fanselow v Yurii Dzhavakian | 4-6,6-7 | |
| Challenger de Pune | 02/20 11:05 | 25 | [313] Sebastian Fanselow v Duje Ajdukovic [125] | 7-5,6-7,3-6 | |
| Challenger de Pune | 02/19 07:30 | 19 | [266] Enrico Dalla Valle v Sebastian Fanselow [313] | 6-4,6-7,3-6 | |
| Challenger de Pune | 02/18 12:35 | 14 | [432] Jonas Forejtek v Sebastian Fanselow [313] | 6-7,4-6 | |
| Challenger de Cleveland | 01/31 16:00 | 26 | [266] Tennys Sandgren v Sebastian Fanselow [313] | 6-0,7-6 | |
| Challenger de Cleveland | 01/30 15:00 | 25 | Sebastian Fanselow v William Grant | 7-6,6-1 | |
| Challenger de Indian Wells | 01/27 18:00 | 28 | [143] Zachary Svajda v Sebastian Fanselow [324] | 6-2,6-4 | |
| Challenger de Indian Wells | 01/26 18:00 | 27 | [473] Learner Tien v Sebastian Fanselow [324] | 6-7,7-5,4-6 | |
| Challenger de Indian Wells | 01/25 18:00 | 26 | Sebastian Fanselow v Trevor Svajda | 6-4,6-4 | |
| Challenger de Indian Wells | 01/23 21:35 | 25 | [324] Sebastian Fanselow v Vasek Pospisil [450] | 6-2,7-5 | |
| Challenger de Indian Wells | 01/15 22:50 | 25 | [400] Giovanni Oradini v Sebastian Fanselow [324] | 6-3,7-6 | |
| Challenger de Oeiras | 01/10 13:55 | 26 | [320] Leandro Riedi v Sebastian Fanselow [324] | 6-3,6-0 | |
| Challenger de Oeiras | 01/09 10:30 | 25 | [324] Sebastian Fanselow v Jaime Faria [394] | Retired | |
| Challenger de Oeiras | 01/08 13:40 | 19 | [299] Tristan Lamasine v Sebastian Fanselow [324] | 4-6,4-6 | |
| Challenger Oeiras Qual | 01/07 16:00 | 14 | [366] Egor Gerasimov v Sebastian Fanselow [321] | 6-7,4-6 | |
| Challenger de Oeiras | 01/01 18:10 | 25 | [255] Cem Ilkel v Sebastian Fanselow [321] | 6-3,3-6,7-5 | |
| Challenger de Maia | 11/28 12:15 | 25 | [324] Sebastian Fanselow v Karl Friberg [385] | 6-3,3-6,4-6 | |
| Challenger de Champaign | 11/16 18:20 | 26 | [328] Sebastian Fanselow v Alex Michelsen [99] | 3-6,2-6 |