| UTR Pro Tennis Series Pazardzhik Women | 2021/05/05 12:00 | Doroteja Petrovic v Ani Vangelova | 1-6,1-6 |
| UTR Pro Tennis Series Pazardzhik Women | 2021/05/04 11:30 | Doroteja Petrovic v M Shkumbova | 3-6,4-5 |
| UTR Pro Tennis Series Pazardzhik Women | 2021/05/03 08:30 | Ralitsa Alexandrova v Doroteja Petrovic | 6-1,5-4 |
| UTR Pro Tennis Series Pazardzhik Women | 2021/05/06 10:00 | Shkumbova, Mirela v Kostova, Elitsa | 1-6,0-6 |
| UTR Pro Tennis Series Pazardzhik Women | 2021/05/04 11:30 | Ralitsa Alexandrova v Kostova, Elitsa | 2-6,0-6 |
| UTR Pro Tennis Series Pazardzhik Women | 2021/05/03 08:30 | Kostova, Elitsa v Ani Vangelova | 6-1,5-0 |
| ITF W60 Bellinzona | 2021/04/05 13:20 | Turati, Bianca v Kostova, Elitsa | 6-4,6-4 |
| ITF W25 Dubai | 2021/04/01 06:25 | Kostova, Elitsa v Hatouka, Yuliya | 2-6,5-7 |
| ITF W25 Dubai | 2021/03/31 07:40 | Lesley Pattinama Kerkhove v Kostova, Elitsa | 2-6,5-7 |
| ITF W25 Dubai | 2021/03/30 10:50 | Kostova, Elitsa v Sharipova, Sabina | 6-4,4-6,6-1 |
| Open d'Australie - Femmes | 2021/01/10 12:55 | Lottner, Antonia v Kostova, Elitsa | 6-4,7-5 |