| Challenger Orlando | 06/07 18:15 | 25 | [315] Sebastian Fanselow v Nicolas Mejia [292] | 2-6,6-7 | |
| Challenger de Little Rock | 05/30 19:55 | 25 | [315] Sebastian Fanselow v Yasutaka Uchiyama [294] | 6-4,3-6,1-6 | |
| Challenger de Shymkent | 05/18 05:35 | 26 | Sergey Fomin v Sebastian Fanselow | 6-3,6-3 | |
| Challenger de Shymkent | 05/17 05:55 | 25 | [318] Sebastian Fanselow v Denis Istomin [303] | 6-1,6-4 | |
| Challenger de Shymkent | 05/14 05:00 | 29 | [358] Emilio Nava v Sebastian Fanselow [397] | 6-4,7-6 | |
| Challenger de Shymkent | 05/13 04:30 | 28 | [329] Ergi Kirkin v Sebastian Fanselow [397] | 6-7,4-6 | |
| Challenger de Shymkent | 05/12 05:50 | 27 | Sebastian Fanselow v Dragos Nicolae Madaras | 6-4,7-6 | |
| Challenger de Shymkent | 05/11 05:55 | 26 | [397] Sebastian Fanselow v Antoine Bellier [311] | 3-6,6-1,6-2 | |
| Challenger de Shymkent | 05/10 09:30 | 25 | [295] Filip C Jianu v Sebastian Fanselow [397] | 3-6,5-7 | |
| Challenger de Shymkent | 05/09 06:00 | 19 | Sebastian Fanselow v Bogdan Ionut Apostol | Retired | |
| Challenger de Shymkent | 05/08 07:50 | 14 | Sebastian Fanselow v Dostanbek Tashbulatov | 7-6,4-6,6-4 | |
| Challenger de Aix-en-Provence | 05/01 12:35 | 14 | [394] Sebastian Fanselow v Mathias Bourgue [316] | 3-6,0-6 | |
| Challenger de Praga | 04/18 08:30 | 19 | [313] Lucas Miedler v Sebastian Fanselow [399] | 6-4,6-3 | |
| Challenger de Praga | 04/17 08:30 | 14 | [403] Sebastian Fanselow v Alexander Erler [395] | 6-1,7-5 | |
| Challenger de Oeiras | 04/05 12:40 | 25 | [396] Sebastian Fanselow v Gastao Elias [173] | 1-6,2-6 | |
| Challenger de Oeiras | 03/27 09:30 | 14 | [483] Noah Rubin v Sebastian Fanselow [393] | 3-6,6-4,6-3 | |
| ITF M25 Loulé | 03/17 16:05 | 25 | Gauthier Onclin v Sebastian Fanselow | 6-3,6-1 | |
| ITF M25 Portimão | 03/09 16:35 | 25 | [260] Marius Copil v Sebastian Fanselow [349] | 6-7,6-3,6-4 | |
| ITF M25 Portimão | 03/08 10:30 | 62 | [349] Sebastian Fanselow v Neil Oberleitner [310] | 6-3,7-6 | |
| ITF M25 Portimão | 03/07 10:00 | 62 | Sebastian Fanselow v Mikel Martinez | 5-7,6-1,10-5 | |
| ITF M25 Portimão | 03/06 09:30 | 62 | Sebastian Fanselow v Batiste Guerra | 6-2,6-0 | |
| ITF M25 Faro | 03/04 10:00 | 26 | Sebastian Fanselow v Jumpei Yamasaki | 2-6,6-3,3-6 | |
| ITF M25 Faro | 03/02 10:00 | 25 | [346] Sebastian Fanselow v Stuart Parker [496] | 6-3,6-3 | |
| ITF M25 Vale Do Lobo | 02/24 12:30 | 26 | Billy Harris v Sebastian Fanselow | 5-7,6-4,6-3 | |
| ITF M25 Vale Do Lobo | 02/23 14:15 | 25 | Miguel Gomes v Sebastian Fanselow | 0-6,0-6 | |
| Challenger de Cherbourg | 02/06 17:30 | 14 | [341] Sebastian Fanselow v Jonas Forejtek [309] | 4-6,6-3,3-6 | |
| Challenger de Cleveland | 02/01 17:15 | 25 | [203] Yasutaka Uchiyama v Sebastian Fanselow [341] | 6-4,6-3 | |
| Challenger de Cleveland | 01/31 19:20 | 19 | [357] Alex Rybakov v Sebastian Fanselow [341] | 4-6,6-7 | |
| Challenger de Cleveland | 01/30 21:40 | 14 | [389] Zachary Svajda v Sebastian Fanselow [348] | 3-6,2-6 | |
| Challenger de Columbus | 01/25 23:15 | 25 | [254] Denis Istomin v Sebastian Fanselow [348] | 7-5,1-6,6-4 |