Howley became a Football League referee in 1954 at the age of 30 and four years later reached the FIFA List. While 35 years of age he took charge of the 1960 FA Cup Final between Wolverhampton Wanderers and Blackburn Rovers, at the time the youngest ever referee to do so.
Howley began his career as a football referee in 1954 at age 30, reaching the FIFA list four years later. At 35, he officiated the 1960 FA Cup Final between Wolverhampton Wanderers and Blackburn Rovers, becoming the youngest ever referee to do so.