Stadium: SPARKS Round: 44
| ITF Women Setubal Qual | 2018/07/07 09:30 | Oliveira, Marta v Kelly Williford | 1-6,2-6 |
| ITF Women Corroios-Seixal | 2018/07/01 11:30 | Westby, Madison v Kelly Williford | 6-3,6-1 |
| Fed Cup, Groupe Mondial | 2018/06/23 18:25 | Kelly Williford v Smith Dias, Yusleydis | 3-6,5-7 |
| Fed Cup, Groupe Mondial | 2018/06/22 16:10 | Marcela Zacarias v Kelly Williford | 6-4,6-1 |
| ITF Women Obidos Qual | 2018/06/04 09:30 | Kelly Williford v Ekaterina Shalimova | 2-6,1-6 |
| ITF Women Obidos Qual | 2018/05/26 09:30 | Pelayo, Luisa v Kelly Williford | 4-6,6-4,6-4 |
| ITF Women Oeiras | 2018/05/20 12:00 | Kelly Williford v Adrover Gallego, Isabel | 4-6,5-7 |
| ITF Women Tiberias | 2018/05/15 07:00 | Kelly Williford v Keren, Yuval | 2-6,1-6 |
| 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 |
| Sharm El Sheikh, Singles W-WITF-EGY-09A | 2018/02/03 08:00 | So, Kumi v Gilchrist, Nadja | 1-6,3-6 |
| Sharm El Sheikh, Singles W-WITF-EGY-09A | 2018/02/02 08:00 | Berfu Cengiz v So, Kumi | 5-7,6-4,4-6 |