Rea was born in Dungannon, County Tyrone and began playing snooker at age 9 in the billiard room of the pub his father managed in Dungannon. He won the All-Ireland Snooker Championship in 1947 and also the Northern Ireland Amateur Championship the same year. Rea became the Irish Professional Champion in 1947 through his defeat of Jack Bates and held the championship until he was defeated by Alex Higgins in January 1972. Rea held Higgins to 5–4 after the first session, but Higgins pulled away to win 28–12, the last scheduled session was not required (and played as an exhibition match).