The club's name derives from its close association with
St. Sebastian's College, Moratuwa, whose students are known as Sebastianites. The club played several first-class and
List A matches at the college ground. Sebastianites Cricket and Athletic Club competed in the first-class
Premier Trophy for 20 seasons from 1990–91 to 2009–10. They played 184 matches, for 38 wins, 50 losses and 96 draws. In the same period they played 87 List A matches, with 37 wins, 42 losses, one tie and seven matches where a result could not be achieved. They played first-class cricket again during the
Premier Trophy Tier B tournament in the 2019–20 season. ==Records==