Thomas Kastanaras (; born 9 January 2003) is a professional footballer who plays as a forward for German Regionalliga Bayern club FC Augsburg II. Born in Germany, he represented Greece internationally on junior levels, before switching allegiance to Germany.
Kastanaras played for the youth teams of TB Untertürkheim and FSV Waiblingen before he joined VfB Stuttgart in 2011. On 3 March 2022, he extended his contract with VfB Stuttgart until June 2025. After leading the club's under-19 side in scoring with 26 goals during the 2021âÂÂ22 season, Kastanaras was promoted to Stuttgart's senior side for the 2022âÂÂ23 season. Kastanaras made his Bundesliga debut for Stuttgart on 17 September 2022 against Eintracht Frankfurt.
On 2 January 2024, Kastanaras joined SSV Ulm in 3. Liga on loan.
On 2 February 2026, Kastanaras signed a one-and-a-half-year contract with FC Augsburg and was assigned to their reserve team FC Augsburg II.
Born in Germany, Kastanaras is of Greek descent. He formerly represented Greece internationally up to the Greece U19s, before switching to represent the Germany U20s in 2022.