| Challenger de Bari | 11/22 10:10 | 19 | Sebastian Fanselow v Matteo Gigante | 2-6,7-5,6-2 | |
| Challenger de Pau | 11/18 19:15 | 26 | [402] Sebastian Fanselow v Holger Vitus Nodskov Rune [108] | 2-6,2-6 | |
| Challenger de Pau | 11/17 12:40 | 25 | [285] Hiroki Moriya v Sebastian Fanselow [402] | 6-7,4-6 | |
| Challenger de Pau | 11/15 11:30 | 19 | [487] Benjamin Lock v Sebastian Fanselow [402] | 4-6,2-6 | |
| Challenger de Pau | 11/14 13:55 | 26 | Robin Bertrand v Sebastian Fanselow | 4-6,3-6 | |
| ITF M25 Villers-lès-Nancy | 11/11 11:00 | 26 | Tristan Schoolkate v Sebastian Fanselow | 7-6,6-3 | |
| ITF M25 Villers-lès-Nancy | 11/10 12:10 | 25 | [225] Petros Tsitsipas v Sebastian Fanselow [396] | 5-7,2-6 | |
| ITF M25 Portimão | 11/01 11:25 | 29 | [361] Paul Jubb v Sebastian Fanselow [446] | 1-6,7-6,4-6 | |
| ITF M25 Portimão | 10/30 12:00 | 28 | [441] Sebastian Fanselow v Maximilian Neuchrist [426] | 6-1,4-6,6-4 | |
| ITF M25 Portimão | 10/29 09:30 | 27 | [441] Sebastian Fanselow v Petros Chrysochos [367] | 6-3,6-0 | |
| ITF M25 Portimão | 10/28 09:00 | 26 | Sebastian Fanselow v Pablo Llamas Ruiz | 6-4,4-6,6-4 | |
| ITF M25 Portimão | 10/27 09:00 | 25 | Sebastian Fanselow v Mehdi Sadaoui | 6-4,6-3 | |
| ITF M25 Quinta Do Lago | 10/21 09:00 | 26 | [438] Sebastian Fanselow v Maximilian Neuchrist [427] | 3-6,6-4,3-6 | |
| ITF M25 Quinta Do Lago | 10/20 08:55 | 25 | [438] Sebastian Fanselow v Rio Noguchi [454] | 6-3,7-6 | |
| ITF M25 Loulé | 10/13 15:40 | 25 | Sebastian Fanselow v Pedro Araujo | 4-6,6-1,0-6 | |
| ITF M25 Setúbal | 10/08 12:05 | 27 | [342] Arthur Cazaux v Sebastian Fanselow [419] | 3-6,6-3,6-3 | |
| ITF M25 Setúbal | 10/07 10:30 | 26 | Illia Stoliar v Sebastian Fanselow | 1-6,0-6 | |
| ITF M25 Setúbal | 10/06 10:00 | 25 | Jumpei Yamasaki v Sebastian Fanselow | 6-4,4-6,4-6 | |
| Challenger de Lisboa | 09/28 09:00 | 25 | [423] Sebastian Fanselow v Nikola Milojevic [141] | 4-6,4-6 | |
| Challenger de Lisboa | 09/27 09:00 | 19 | [442] Jacopo Berrettini v Sebastian Fanselow [423] | 6-4,5-7,2-6 | |
| Challenger de Lisboa | 09/26 09:00 | 14 | [239] Marco Bortolotti v Sebastian Fanselow [421] | 2-6,2-6 | |
| Challenger de Braga | 09/20 09:00 | 19 | [350] Nikolas S Izquierdo v Sebastian Fanselow [421] | 6-4,1-6,6-3 | |
| Challenger de Braga | 09/19 10:25 | 14 | Jaime Faria v Sebastian Fanselow | 0-6,2-6 | |
| ITF M25 Sintra | 09/15 15:35 | 25 | Adria S Barrera v Sebastian Fanselow | 6-4,6-4 | |
| ITF M25 Sintra | 09/08 10:40 | 25 | Luca Potenza v Sebastian Fanselow | 6-4,6-4 | |
| ITF M25 Bagneres-De-Bigorre | 09/01 07:30 | 25 | Millen Hurrion v Sebastian Fanselow | 2-6,7-5,7-6 | |
| Challenger de Poznan | 07/25 10:30 | 14 | [414] Sebastian Fanselow v Lucas Gerch [444] | 2-6,5-7 | |
| Challenger de Poznan | 07/25 10:20 | 14 | Sebastian Fanselow v Corentin Denolly | Cancelled | |
| ITF M25 Bourg-en-Bresse | 06/29 13:00 | 25 | [373] Viktor Durasovic v Sebastian Fanselow [402] | 1-6,7-6,6-2 | |
| Challenger de Milán | 06/20 13:15 | 14 | [392] Sebastian Fanselow v Camilo Ugo Carabelli [300] | 6-3,2-6,2-6 |