 Farrell made 28 appearances and scored 3 goals for the FAI XI.While still at Shamrock Rovers, he captained the FAI XI on his international debut on 16 June 1946, against Portugal.On 21 September 1949, together with Johnny Carey and Con Martin, he was a member of the FAI XI that defeated England 2–0 at Goodison Park, becoming the first non-UK team to beat England at home.