All Blacks keep their best lock
That means the most influential second row forward in the country will be available to the All Blacks, Crusaders and Canterbury for at least another three years.
"When I considered whether my immediate playing future was here in New Zealand and Christchurch, I didn't need to look far for the answer," Whitelock said.
"My wife Hannah and I have recently welcomed a new addition to our family, I am still genuinely excited to be playing for these teams, and I feel like there is still plenty more to achieve," he added.
"There is more than enough to motivate me to keep playing and performing for these teams, so I am thrilled and honoured to have re-signed with New Zealand Rugby, the Crusaders and Canterbury through to 2020," Whitelock added.
The 28-year-old Whitelock has played 84 Tests for the All Blacks since making his Test debut back in 2010 against Ireland in New Plymouth.
He made an immediate impact, scoring two tries in that first Test.
In 2011 he was selected in the All Blacks' World Cup squad and started every game bar the first pool match.
At the 2015 World Cup he played in every game.
He became the most capped lock in his 80th Test against Argentina last year, overtaking Ian Jones, and is currently the 11th most capped All Black of all time.
Whitelock is a Super Rugby centurion, making his Super debut in 2010.
The son of former Junior All Black, Braeden Whitelock, he is one of four Whitelock brothers to have represented Canterbury and the Crusaders. His cousin Ben Funnell is also a current member of both squads.
The Whitelock brothers and Funnell all moved south from Palmerston North to attend university in Canterbury and went on to play for the Canterbury provincial side. Sam first appeared for Canterbury in 2008.
All Black coach Steve Hansen said having Whitelock's services for the next few years was a major boost for the national side.
"On behalf of New Zealand Rugby, as well as all New Zealand rugby fans, I want to congratulate Sam and his wife Hannah on his decision," Hansen said.
"He's a world-class lock and together with Brodie Retallick forms one of the best international locking partnerships in world rugby at present.
"Sam is also great contributor to our environment. He thinks a lot about the game, is a flexible thinker, leads very well within the group and has become a very, very important component in the All Blacks.
"Once again, it's great to have another one of our key men re-sign with New Zealand Rugby," Hansen added.
Retaining Whitelock's formidable skillset and leadership qualities for the immediate future would also be invaluable for the Crusaders, according to coach Scott Robertson.
"Sam is an incredibly important member of this team and has been an inspiration as our captain this season. He leads through his actions and has huge mana amongst the team. The example he sets both on and off the field is exemplary, so we are stoked that we will continue to have his positive influence in our environment," Robertson said.
Whitelock joins All Blacks Vice-Captain Ben Smith in re-signing through to 2020, while Owen Franks, Israel Dagg, Brodie Retallick, Aaron Smith, Julian Savea, Dane Coles, Sonny Bill Williams, Joe Moody, Patrick Tuipulotu, Liam Squire and Liam Coltman have all inked deals through to 2019.
