The club were previously members of the Scottish Junior Football Association, playing in the Fife League followed by the East Region Superleague.

In December 2017 the club became a full SFA member, making them eligible to enter the Scottish Cup and move up through the pyramid system.

[8] Kelty looked to move away from being a junior side after winning the East Region Super League for the second time in 2017.

[13] The 2019–20 Lowland League season was ended with immediate effect on 13 April 2020 due to the COVID-19 pandemic with Kelty Hearts being declared champions on a points per game average based on the current standings.

[14][15] For the second consecutive season, Kelty were declared champions of the 2020–21 Lowland Football League on a points per game formula due to the ongoing COVID-19 pandemic.

Facing Scottish Premiership side and cup holders St Johnstone, Kelty won 1–0 after extra time at home in front of a sold-out crowd, thanks to a goal by Kallum Higginbotham.

Kelty were promoted to Scottish League One at the first attempt with five games of the season remaining on 26 March 2022 when they beat Stenhousemuir 1–0, and nearest challengers Annan Athletic lost their match.

[8][24] Upon gaining promotion to the SPFL, Kelty compete in the bigger Fife derbies, with their closest rivals being Cowdenbeath, the two separated by just 2.7 miles (4.3 km).