"I'm now looking forward to spending summer with my family and friends, and coming back ready go to again in 2022."
All Blacks Head Coach Ian Foster, who selected Cane as his captain last year, said: "We are thrilled that Sam has made a long-term commitment to New Zealand Rugby.
"He's an instrumental part of the All Blacks leadership group in his role as captain and I know that following a year in which he missed a lot of rugby with his significant injury, he is fully committed to being at his very best in 2022 and beyond, which is exciting.
"We're delighted for him and Harriet."
NZR General Manager Professional Rugby and Performance Chris Lendrum added: "We are blessed to have a person of Sam's calibre playing in New Zealand and he has been an exceptional and loyal player since coming into the professional ranks as a young man.
"He's one of the most respected players and voices in our game and all the teams that he has played for have benefitted from his outstanding play and leadership. We're delighted that he has chosen to stay with New Zealand Rugby for four more years."
As part of his contract, Cane has the option of taking a non-playing or playing break from the New Zealand game in 2024.
Chiefs Head Coach Clayton McMillan said: "Sam is an exceptional player and highly respected leader, who has a great rapport with both coaches and players. He is passionate about the teams he is involved with and continues to demonstrate that through his ultra-consistent performances on the field.
"We are incredibly fortunate to have his services and look forward to seeing him continue to further his already impressive career."