The 27-year-old has suffered repeated shoulder injuries in recent seasons, and is recovering from reconstruction surgery at the moment.
He will miss the Chief’s Super Rugby opener against the Highlanders on Feb. 22, having had further minor surgery last week.
“I love being a Chief, but it is no secret that I have had my fair share injuries which have forced me to make some very hard decisions about my future and make the most of the opportunities while I can,” he told the Waikato Times.
Capped 27-times for the All Blacks, he has signed a two-year contract with the Toshiba club beginning at the end of the Super Rugby season in August.
He made his All Blacks debut in 2008, appearing at both centre or on the wing, where he featured during the 2011 World Cup.
Kahui made over 50 appearances for the Chiefs, with coach Dave Rennie hailing his contribution.
“I have been really impressed with him as a man, as a player and as a leader within our group,” Rennie said.
“He has an opportunity to set himself up for his future and we are fully supportive of what he is doing and hope to get him back for 2015.”
He also played for the Waikato NPC side and for the Highlanders as a drafted injury replacement in 2006.