 Stewart's first state representative selection for New South Wales came in 2001 in the men's senior eight who contested the King's Cup at the Interstate Regatta within the Australian Rowing Championships From 2001 to 2004 and in 2008 he rowed in New South Wales men's senior eights competing for the King's Cup at the Interstate Regatta.He stroked the 2003, 2004 and 2008 eight and saw King's Cup victories in 2004 and 2008.Stewart made his Australian representative debut in 1995 aged eighteen, competing at the World Rowing U23 Championships in Groningen in the men's eight who finished in eighth place.