| ITF M25 - Rancho Santa Fe | 01/15 21:55 | 25 | Alafia Ayeni v Sebastian Fanselow | 3-6,2-6 | |
| ITF M25 - Rancho Santa Fe | 01/14 18:55 | 54 | Sebastian Fanselow v Alexander Lebedev | 7-5,2-6,10-3 | |
| ITF M25 - Los Angeles | 01/08 18:30 | 25 | [366] Alexander Ritschard v Sebastian Fanselow [492] | 6-3,6-0 | |
| Challenger - Houston | 11/11 22:00 | 24 | Nick Chappell v Sebastian Fanselow | 6-1,3-6,7-6 | |
| ITF M25 - Malibu | 11/07 20:15 | 26 | [298] Alejandro Gomez v Sebastian Fanselow [394] | 6-4,7-6 | |
| ITF M25 - Malibu | 11/06 17:00 | 25 | Alexandre Rotsaert v Sebastian Fanselow | 5-7,3-6 | |
| Challenger Playford 2 | 10/29 02:20 | 25 | [405] Sebastian Fanselow v Yosuke Watanuki [285] | 6-7,2-6 | |
| Challenger Playford 2 | 10/28 02:05 | 24 | Sebastian Fanselow v Cameron Green | 6-4,7-6 | |
| Challenger - Traralgon | 10/22 02:25 | 25 | [236] Sasikumar Mukund v Sebastian Fanselow [375] | 7-6,6-3 | |
| Challenger - Traralgon | 10/21 01:20 | 24 | [359] Brydan Klein v Sebastian Fanselow [371] | 4-6,1-6 | |
| Challenger - Fairfield | 10/08 17:00 | 24 | [315] Sebastian Korda v Sebastian Fanselow [343] | 6-4,7-6 | |
| ITF M25 Norman | 10/05 19:55 | 28 | [480] Michael Geerts v Sebastian Fanselow [342] | 6-3,6-3 | |
| ITF M25 Norman | 10/04 16:45 | 27 | Reese Stalder v Sebastian Fanselow | 2-6,1-6 | |
| ITF M25 Norman | 10/03 15:00 | 26 | Strong Kirchheimer v Sebastian Fanselow | 4-6,6-3,5-7 | |
| ITF M25 Norman | 10/02 16:55 | 25 | Liam Caruana v Sebastian Fanselow | Retired | |
| Challenger - Tiburon | 09/23 19:00 | 24 | [498] Carlos Gomez-Herrera v Sebastian Fanselow [338] | 6-4,4-6,6-2 | |
| ITF M25 Houston | 09/18 19:00 | 25 | Sebastian Fanselow v Tadeas Paroulek | 5-7,6-3,4-6 | |
| Challenger L'Aquila | 08/19 12:30 | 24 | [333] Sebastian Fanselow v Peter Torebko [316] | 5-7,3-6 | |
| Challenger - Meerbusch | 08/12 09:35 | 24 | [329] Sebastian Fanselow v Scott Griekspoor [401] | 3-6,4-6 | |
| Challenger - Amersfoort | 07/18 13:20 | 26 | Sebastian Fanselow v Igor Sijsling | 5-7,3-6 | |
| Challenger - Amersfoort | 07/17 16:30 | 25 | [190] Tallon Griekspoor v Sebastian Fanselow [302] | 6-1,4-6,3-6 | |
| Challenger - Amersfoort | 07/15 16:30 | 24 | Ryan Nijboer v Sebastian Fanselow | 4-6,2-6 | |
| Challenger Ludwigshafen | 07/03 16:00 | 25 | [148] Dustin Brown v Sebastian Fanselow [305] | 6-3,6-2 | |
| Challenger Ludwigshafen | 07/01 11:50 | 24 | [202] Alexey Vatutin v Sebastian Fanselow [305] | 7-5,2-6,6-7 | |
| Challenger - Milaan | 06/27 14:00 | 26 | [343] Aslan Karatsev v Sebastian Fanselow [315] | 6-4,6-2 | |
| Challenger - Milaan | 06/26 13:30 | 25 | [315] Sebastian Fanselow v Paolo Lorenzi [107] | 6-4,7-5 | |
| Challenger - Milaan | 06/24 15:30 | 24 | Sebastian Fanselow v Christopher Heyman | 7-5,7-6 | |
| Challenger - Bratislava | 06/19 08:00 | 25 | [320] Sebastian Fanselow v Alexey Vatutin [206] | 4-6,4-6 | |
| Challenger - Bratislava | 06/17 09:20 | 24 | [320] Sebastian Fanselow v Alex Molcan [330] | 7-6,6-3 | |
| Challenger - Morelos | 02/19 18:00 | 25 | [338] Matias Franco Descotte v Sebastian Fanselow [304] | 6-4,6-2 |