İstanbul Başakşehir Futbol Kulübü is a Turkish professional football club based in the Başakşehir district of Istanbul. The club is better known as İstanbul Başakşehir or, due to sponsorship, Medipol Başakşehir.
The club was founded in 1990 as İstanbul Büyükşehir Belediyespor. They first reached the highest level in Turkish Football in 2007–08.
They play their home games at the Fatih Terim Stadium which has a capacity of 17,156 in Istanbul and is owned by the Ministry of Youth and Sports.
The club is one of five Süper Lig teams based in Istanbul, along with Fenerbahçe, Galatasaray, Beşiktaş, and Kasımpaşa. In the 2016–17 season, they participated in the Süper Lig, Turkish Cup, and UEFA Europa League.
In the 2017–18 season, they reached the play-off round of the UEFA Champions League qualifying round. They won their first top-flight title in the 2019–20 season.