Kingston made his first grade debut for Cronulla against the Newcastle Knights at Shark Park in round 19 of the 2005 NRL season.

In round 11 he became a regular part of the Parramatta squad coming off the bench to replace Matt Keating.

Kingston was a major contributor in the club's late-season streak that saw them make it to the 2009 NRL Grand Final.

In round 4 though, Kingston was selected to play Half-Back by coach Matthew Elliot while Luke Walsh was out with a shoulder injury.

In 2014, Kingston captained Penrith's reserve grade side as they won the Intrust Super Premiership NSW competition defeating Newcastle 48–12 in the final.