[1] He made his first-class cricket debut for Kent in September 2017 in the club's final County Championship match of the season, having signed his first professional contract at the end of August.

[4][5] He was born at Kalgoorlie in Western Australia but grew up mainly in New South Wales, first in Sydney and then in Lorn near Newcastle, living on a turf farm.

[4][10][11] Stewart moved to play for Adelaide University Cricket Club in South Australia during the 2016/17 season and returned to Kent in 2018.

[4][10] After making his first-class debut at the end of the 2017 season, he made his first List A appearance during Kent's pre-season campaign at the 2017–18 Regional Super50 competition in the West Indies, taking three wickets against Guyana at the Coolidge Cricket Ground in Antigua.

[16][17] In May 2021, it was announced that Stewart would play for the Italian cricket team in the final stage of the 2021 ICC Men's T20 World Cup Europe Qualifier tournament.