Hilson, who had featured a handful of times for Dundee United's under-19 side, made his professional debut in October 2009 as a substitute in the Scottish Premier League match against Hamilton Academical. He won the Under-19 Scottish Premier League player of the season for 2009/10. and joined Forfar Athletic on loan in August 2010, scoring on his league debut. Hilson was again loaned to Forfar in 2012. He was sent off for foul and abusive language on 28 April 2012. He started a third loan spell at Forfar in December 2012. He then returned for a fourth loan spell at the Loons in August of that year, joining until the end of January 2014 but the loan was extended until the end of the season where he finished joint top goalscorer with Gavin Swankie on 13 goals. During the fourth loan spell, he made his 100th appearance for the Loons, making 113 in total during his time.
He was released by Dundee United at the end of his contract on 4 June 2014, and then signed for Forfar on a permanent deal on 3 July 2014.