2009-10: Kurtis MacDermid played minor midget hockey with the Grey-Bruce Highlanders in Central Ontario. MacDermid was selected by the Owen Sound Attack in the seventh round (139th overall) of the 2010 OHL Priority Draft.
2010-11: MacDermid skated for the Owen Sound Grays in the GOJHL. He was the leading scorer among defensemen for the Grays; finishing with 6 goals and 16 assists with 124 penalty minutes while playing all 51 games. The Grays finished last in the Midwestern Conference; winning just four games.
2011-12: MacDermid made his OHL debut; appearing in nine games due to a bout with mononucleosis, a season-ending injury in January and the presence of several veteran defensemen in the Owen Sound lineup. He had 2 assists and was an even plus/minus with 7 penalty minutes. He also returned to the Grays, skating in 20 games, and had 3 goals with 6 assists and 80 penalty minutes. The Greys missed the GOJHL playoffs; finishing last in the Midwestern Conference. MacDermid attended the Kings' prospect camp in July after passing through the 2012 NHL Draft without being selected and signed a three-year entry-level contract with the Kings in September, 2012.