Born in New Brunswick, New Jersey, Farrell grew up in Point Pleasant Beach, New Jersey and attended Point Pleasant Beach High School. He committed to Boston College as a senior. However, his plans changed when the college fired Steve Donahue as the basketball coach in 2014. Instead, Farrell signed with Notre Dame in March 2014 because his grandfather Bob Farrell attended the school and frequently told stories of his time there. Farrell was the Asbury Park Press 2014 boys basketball player of the year after averaging 19.5 points, 5.9 assists, 3.8 rebounds and 3.9 steals per game as a senior. He led Point Beach to a 29-2 record and the second consecutive Shore Conference Class B Central division title. Farrell scored 1,431 points and dished out 545 assists in his high school career.
College career
Farrell joined the starting lineup for the postseason as a sophomore and helped the Fighting Irish reach the Elite Eight. He averaged 14.1 points and 5.4 assists per game as a junior while shooting 42 percent from 3-point range as Notre Dame finished 26-10 and advanced to the NCAA Tournament’s second round. He was an All-ACC Honorable Mention as a junior. Farrell missed several games in early January 2018 with a right ankle sprain, leaving Notre Dame without their two best players since Bonzie Colson fractured his foot. On February 17, Farrell scored a career-high 37 points and made a school-record 10 3-pointers with seven assists to help Notre Dame defeat Boston College 84-67. He made a long 3-pointer to give Notre Dame the lead with eight seconds remaining in a win against Wake Forest on February 24 and finished with 21 points. In the game, Farrell surpassed the 1,000 point mark for his career. At the conclusion of the regular season, Farrell was named to the All-ACC Third Team. As a senior, Farrell averaged 16.3 points and 5.3 assists per game. After the season, he signed with sports agentKeith Glass and participated in the Portsmouth Invitational Tournament.
On October 10, 2018, Farrell signed with the Philadelphia 76ers. Farrell was waived on October 12. He was added to the Delaware Blue Coats training camp roster.
For the 2019–20 season, Farrell joined the Austin Spurs.
Northern Arizona Suns (2020–present)
On January 15, 2020, the Northern Arizona Suns announced that they had acquired Farrell from the Austin Spurs for the returning right to Peter Jok. He suffered a hip injury in late February and missed several games.
