Luxembourg: W15 Esch/Alzette - Doubles - Main |
| Semi-finals | Daems J./Firman A. | Hobgarski K./Kostic T. | 2:0 (6:3, 7:5) | details | 12.01.2024 |
| Quarter-finals | Kuparev A./Sato H. | Hobgarski K./Kostic T. | 0:2 (5:7, 1:6) | details | 11.01.2024 |
Egypt: W15 Sharm ElSheikh 16 - Doubles - Main |
| Final | Kostic T./Shubladze A. | Suvirdjonkova D./Zelinskaya D. | 1:2 (5:7, 6:2, 11:13) | details | 04.11.2023 |
| Semi-finals | Samir S./Shalimova E. | Kostic T./Shubladze A. | 0:2 (3:6, 4:6) | details | 03.11.2023 |
| Quarter-finals | Kostic T./Shubladze A. | Lazarenko K./Shan Y. | WO. | details | 02.11.2023 |
| 1/8-finals | Solomatina A./Van Emst S. | Kostic T./Shubladze A. | 0:2 (0:6, 3:6) | details | 31.10.2023 |
Spain: W25 Seville - Doubles - Main |
| Quarter-finals | Cavalle-Reimers Y./Fita Boluda A. | Kostic T./Simunyu C. | 2:0 (6:1, 6:3) | details | 11.10.2023 |
| 1/8-finals | Kostic T./Simunyu C. | Santos Sanchez L./Villanueva Morillo L. | 2:1 (2:6, 6:2, 10:8) | details | 10.10.2023 |
Austria: W15 Bad Waltersdorf - Doubles - Main |
| 1/8-finals | Kostic T./Tothova E. | Kargina V. M./Odorizzi C. | 1:2 (6:2, 4:6, 6:10) | details | 03.10.2023 |
Austria: W60 Vienna - Doubles - Main |
| 1/8-finals | Kostic T./Michalitsch A. | Abduraimova N./Cortez Llorca L. | 0:2 (0:6, 3:6) | details | 05.09.2023 |
Romania: W15 Brasov - Doubles - Main |
| 1/8-finals | Kostic T./Ogescu S. | Ionescu I. A./Safta A. | 1:2 (612:7, 6:2, 9:11) | details | 22.08.2023 |
Georgia: W15 Tbilisi - Doubles - Main |
| 1/8-finals | Kostic T./Simunyu C. | Iudenko I./Rasskovskaia L. | 0:2 (3:6, 5:7) | details | 01.08.2023 |
France: French Open - Doubles - Main |
| 1/8-finals | Korneeva A./Saito S. | Kostic T./Sonobe W. | 2:0 (6:3, 6:2) | details | 06.06.2023 |
| 1/16-finals | Kostic T./Sonobe W. | Esquiva Banuls C./Pawlikowska Z. | 2:1 (2:6, 7:63, 10:5) | details | 05.06.2023 |