The 27-year-old has put pen to paper on a deal until the summer of 2025.
Kingsley follows defensive partner Craig Halkett and Craig Gordon in committing his future to Hearts.
Since joining as a free agent in 2020 after leaving Hull City, the defender has been one of the club’s best and most consistent players.
This season he has been a key cog in the club’s positive performances and the 3-4-3 system the team operate under Robbie Neilson.
“It’s fantastic to get Stephen committed to Hearts for another three seasons," the Tynecastle Park boss told the club's website.
“He’s gone from strength to strength since he arrived here and he’s undoubtedly one of the country’s top defenders.
“It’s a big boost for us and everyone here is delighted to get it sorted.”
The club’s sporting director welcomed the news of Kingsley's new deal and told fans “there is definitely more to come”.
“Stephen’s made such a big impact since joining the club and he’s a really popular figure behind the scenes,” he said.
“His quality on the pitch is there for all to see and I’m sure the fans will be as happy as we are to get this deal completed.
“Stephen’s been a crucial part of the project here at Hearts and the exciting thing is that we’re only in the early stages. The club is in a strong position and there is definitely more to come.”