Aged 16, Kingsley made his first-team debut for Falkirk on 12 April 2011 in a 2–1 win versus Partick Thistle in the Scottish First Division.
[4] On 18 February 2015, Kingsley joined English League One side Yeovil Town on a month's emergency loan which was later extended until the end of the season.
[5] Kingsley played in numerous positions in his 12 appearances for the Glovers including left-back, centre-back and midfield, and received praise for his versatility from Yeovil boss Terry Skiverton.
[14] Kingsley quickly became known as an efficient taker of the direct free kick, scoring several long-range strikes for Hearts since joining.
[15] He scored what proved to be the match-winning goal in the semi-final of the 2021–22 Scottish Cup – an Edinburgh derby against Hibernian – from a 30-yard free kick, albeit assisted with a wall pass from Liam Boyce.
He was selected for the squad for the 2014 UEFA European Under-19 Football Championship qualification matches in October, playing in the third game against Switzerland.
[19] Kingsley was recalled to the national team squad in September 2022 as a replacement for the injured Kieran Tierney and Scott McKenna.