Stadium: Court C1 Round: 54 Ground: Hardcourt outdoor
| ITF Women Figueira Da Foz Qual | 2018/07/16 12:00 | Cristina Bucsa v So, Kumi | 6-1,6-0 |
| ITF Women Setubal Qual | 2018/07/08 13:00 | Williford, Kelly v So, Kumi | 2-6,6-7 |
| ITF Women Corroios-Seixal | 2018/07/05 11:00 | Eden Silva v So, Kumi | 6-2,6-3 |
| ITF Women Corroios-Seixal | 2018/07/03 11:30 | Fayol, Clemence v So, Kumi | 6-2,4-6,3-6 |
| Sharm El Sheikh, Singles W-WITF-EGY-09A | 2018/04/10 08:00 | So, Kumi v Iryna Shymanovich | 4-6,4-6 |
| Sharm El Sheikh, Singles W-WITF-EGY-09A | 2018/04/05 11:00 | Gabueva, Angelina v So, Kumi | 6-2,6-3 |
| Sharm El Sheikh, Singles W-WITF-EGY-09A | 2018/04/04 08:00 | So, Kumi v Rutuja Bhosale | 6-2,6-2 |
| Yokohama, Singles Qualifying W-WITF-JPN-01B | 2018/03/04 02:30 | Harriet Dart v So, Kumi | 6-3,6-3 |
| ITF Women Taipei | 2018/07/24 03:55 | Chan, Chin-Wei v Takahata, Kotomi | 4-6,6-3,6-3 |
| ITF Women Astana Qual | 2018/07/14 10:45 | Kruzhkova, Daria v Takahata, Kotomi | 6-2,6-1 |
| ITF Women Tianjin Qual | 2018/07/09 02:00 | Takahata, Kotomi v Mei Xu Wu | 3-6,6-2,2-6 |
| ITF Women Tianjin Qual | 2018/07/08 06:35 | Takahata, Kotomi v Yang, Qian | 6-0,6-2 |
| ITF Women Daegu | 2018/06/21 01:00 | Su Jeong Jang v Takahata, Kotomi | 6-3,7-5 |
| ITF Women Daegu | 2018/06/20 05:45 | Takahata, Kotomi v Koike, Satsuki | 6-4,7-5 |
| ITF Women Daegu Qual | 2018/06/19 01:00 | Takahata, Kotomi v Hong, Seung-Yeon | 6-4,3-6,6-3 |
| ITF Women Daegu Qual | 2018/06/18 03:30 | Takahata, Kotomi v Ahn, Yu Jin | 6-1,6-4 |