| WTA Montevideo | 11/22 21:30 | 25 | Grant, Guillermina v Ipek Oz | 2-6,1-6 | |
| Billie Jean King Cup | 07/30 15:25 | 2 | Romina Ccuno v Grant, Guillermina | 3-6,3-6 | |
| Billie Jean King Cup | 07/28 16:30 | 2 | Grant, Guillermina v Rahmanparast, Ariana | 6-0,6-0 | |
| Billie Jean King Cup | 07/27 15:20 | 2 | Grant, Guillermina v Junmoke James | 6-2,6-0 | |
| Billie Jean King Cup | 07/26 16:30 | 2 | Grant, Guillermina v Espinal Sanchez, Natalie Gabriela | 7-6,6-3 | |
| Billie Jean King Cup | 07/25 15:15 | 2 | Grant, Guillermina v Chambers, Hannah | 6-3,6-3 | |
| WTA Montevideo | 11/16 20:15 | 25 | Grant, Guillermina v Maria Lourdes Carle | 6-7,2-6 | |
| Billie Jean King Cup | 06/26 19:00 | - | Roemer, Charlotte v Grant, Guillermina | 7-5,3-6,6-3 | |
| Billie Jean King Cup | 06/25 15:00 | - | Clarke, Sydney v Grant, Guillermina | 2-6,3-6 | |
| Billie Jean King Cup | 06/24 17:10 | - | Grant, Guillermina v Rahmanparast, Ariana | 6-3,6-2 | |
| Fed Cup, Groupe Mondial | 04/19 14:00 | - | Morales, Melissa v Grant, Guillermina | 7-5,5-7,6-4 | |
| Fed Cup, Groupe Mondial | 04/18 14:00 | - | Hernandez, Isid v Grant, Guillermina | 4-6,1-6 |
Guillermina Grant (born 22 June 2002) is a Uruguayan tennis player, who played at the Uruguay on the Fed Cup since 2017.
Grant has a career-high ITF juniors ranking of 31, achieved on 2 March 2020.
In December 2020, Grant signed with the Georgia Bulldogs college team for the 2021-22 season.