Stadium: Hard 20 Round: 27 Ground: Hardcourt outdoor
| Challenger Nottingham | 2023/06/11 15:40 | Harry Wendelken v Alex Michelsen | 6-4,3-6,5-7 |
| Challenger Surbiton | 2023/06/06 10:00 | Bu Yunchaokete v Harry Wendelken | 7-6,7-5 |
| Challenger Surbiton | 2023/06/05 10:00 | Pierre-Hugues Herbert v Harry Wendelken | 4-6,6-7 |
| Challenger Surbiton | 2023/06/04 12:25 | Harry Wendelken v Li Tu | 7-6,6-3 |
| ITF M15 Kalmar | 2023/05/16 12:45 | Harry Wendelken v Max Dahlin | 6-4,3-6,6-7 |
| ITF M25 Nottingham | 2023/05/04 14:05 | Daniil Glinka v Harry Wendelken | 6-2,6-2 |
| ITF M25 Nottingham | 2023/05/03 09:00 | Harry Wendelken v Sean Hodkin | 6-2,6-2 |
| ITF M25 Nottingham | 2023/04/25 12:40 | Harry Wendelken v Stuart Parker | 4-6,5-7 |
| UTR Pro Hilversum | 2023/06/06 06:00 | Guy Den Heijer v Victor Sklenka | 7-6,4-6,5-3 |
| UTR Pro Hilversum | 2023/06/05 07:30 | Guy Den Heijer v Ivan Sergeyev | 0-6,2-6 |
| ITF M15 Antalya | 2023/04/30 07:00 | Guy Den Heijer v Juan Manuel La Serna | 6-7,1-6 |
| ITF M15 Antalya | 2023/04/02 07:00 | Guy Den Heijer v Niels Visker | 1-6,6-4,3-10 |
| ITF M25 Portimao | 2023/03/14 11:00 | Guy Den Heijer v Mikel Martinez | 1-6,2-6 |
| ITF M25 Portimao | 2023/03/13 15:35 | Guy Den Heijer v Miguel Pereira Lopes | 6-1,6-3 |
| ITF M25 Quinta Do Lago | 2023/03/09 17:20 | Jesper De Jong v Guy Den Heijer | 6-3,6-1 |
| ITF M25 Quinta Do Lago | 2023/03/09 13:30 | Sean Hodkin v Guy Den Heijer | 4-6,4-6 |