Sofia Costoulas
Sofia Costoulas is a Belgian professional tennis player. She has career-high rankings of No. 173 in singles, achieved on 8 September 2025, and No. 229 in doubles, achieved on 25 September 2023.
Early life
Costoulas was born in Genk to a Greek-Congolese father and a Belgian mother. Her father was a professional footballer who played for Sint-Truidense V.V., K. Patro Eisden Maasmechelen, and C.S. Visé. She began playing tennis at the age of four. She trained at her local club in Genk, the Kim Clijsters Academy, and the Justine Henin Academy.Junior career
In July 2021, she and Laura Hietaranta reached the girls' doubles final of Wimbledon, but lost to Kristina Dmitruk and Diana Shnaider. In September 2021, she reached the girls' singles third round of the US Open.In January 2022, she won the J1 Traralgon Tennis International, defeating Kayla Cross in the final. Later that month, she reached the girls' singles final of the Australian Open, but lost to Petra Marčinko. In April 2022, she won back-to-back J1 titles in Vrsar and Plovdiv. The following month, she also won the JA International HTV Junior Open in Offenbach am Main.
Professional career
In December 2021, she reached back-to-back W15 finals in Monastir. In February 2022, she reached the semifinals of the W25 Copa Banco in Guayaquil. In October 2022, she won her first professional doubles title at the W25 tournament in Hua Hin, partnering Punnin Kovapitukted.In April 2025, she won her biggest title to-date at the W75 Ladies Open Calvi Eaux de Zilia, defeating Tessah Andrianjafitrimo in the final. The following month, she reached the second round of the qualifying competition of the French Open, but ultimately failed to advance into the main draw.
Grand Slam singles performance timeline
| Tournament | 2025 | W–L |
| Australian Open | A | 0–0 |
| French Open | Q2 | 0–0 |
| Wimbledon | Q1 | 0–0 |
| US Open | Q1 | 0–0 |
| Win–loss | 0–0 | 0–0 |
ITF Circuit finals
Singles: 12 (4 titles, 8 runner-ups)
| Result | W–L | Date | Tournament | Tier | Surface | Opponent | Score | |||||||||||||||
| Loss | 0–1 | Feb 2021 | ITF Sharm El Sheikh, Egypt | W15 | Hard |  Doubles: 11 (3 titles, 8 runner-ups)
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