He spent one season at Halifax; which proved to be highly successful on an individual level, with Harsley ending up as their top scorer with twelve goals from fifty games; however the team performed extremely poorly and they were relegated out of the English Football League, a full nine points below Bristol Rovers.
During his time at Halifax, Harsley had a standout season, scoring 12 goals in 50 games, but unfortunately, the team's overall performance was disappointing, leading to their relegation from the English Football League by a margin of 9 points compared to Bristol Rovers.