Howitt's first notable TV role was in the 1984-85 series of Yorkshire Television's long-running programme for schools How We Used To Live, where he starred alongside Brookside Actress Sue Jenkins. However, he is much better known for playing Joey Boswell in the BBC TV series Bread. In 1998, he wrote and directed his first film, Sliding Doors (1998). Since then, he has directed several films, including Antitrust (2001), Johnny English (2003), Laws of Attraction (2004), and Dangerous Parking (2008). He adapted the latter film from the novel by Stuart Browne, as well as produced and directed it, and played the lead role. He also directed the 2014 film Reasonable Doubt - the film was shot in Winnipeg, Canada in December 2012.