The pair signed for the Panthers during the off-season, initially on year-long deals but the club have opted to sign both players until 2013.
The move will give Penrith ample cover for several positions including, hooker, halfback and five-eighth.
Club chief executive Michael Leary said the deals will give the Panthers ample cover.
“Our strategy has been to lock in those key positions long term,” he said.
“Keeping those players together will enable us consistency as we continue sign players.
Burns joined the Panthers having played 72 first grade games between Manly and the Cowboys while Kingston played 78 first grade games between Cronulla and Parramatta before joining the club.