Harris was an umpire in Minor Counties matches involving Devon from 1979 to 1982 and from 1981 he started acting as umpire in a few first-class matches too. In 1983 he was appointed for the regular first-class and List A umpires for English cricket and he remained there, officiating in 288 first-class and 308 List A games, until he retired at the end of the 2000 season. He acted as reserve umpire in one Test match in his final season as an umpire.
