Borna Sosa (born 21 January 1998) is a Croatian professional footballer who plays for VfB Stuttgart and the Croatia national under-21 team as a left back.
Sosa was born in the Prečko neighbourhood of Zagreb to Herzegovinian Croat parents from Gradac near Posušje. He is a youth prospect of Dinamo Zagreb. He made his Prva HNL debut on 7 March 2015 against NK Zagreb in a 2–0 home win, starting and playing full 90 minutes.
On 14 May 2018, Borna Sosa signed a five-year-contract with VfB Stuttgart, enabling him to transfer to Stuttgart on 1 July 2018. On 27 November 2020, he extended his contract until 2025.
In May 2018, he was named in Zlatko Dalić’s preliminary 32-man squad for the 2018 World Cup in Russia but did not make the final 23. He was named in Nenad Gračan’s squad for the Under-21 Euro 2019 and Igor Bišćan’s squad for the Under-21 Euro 2021.