The 26-year-old, who was off-contract with the Highlanders, made 21 appearances for the club since his debut in 2020.
He was in good touch this season but managed only seven Super Rugby outings before he succumbed to a knee injury.
Selby-Rickit returned to play for the Maori All Blacks against Ireland and for Bay of Plenty in the NPC.
Coach Clayton McMillan was looking forward to seeing him in action for the Chiefs.
"Manaaki’s form for Bay of Plenty throughout the Bunnings Warehouse NPC season was outstanding.
"I thought he was dominant at lineout time, had an outstanding work rate, and a great physical presence," he said.
He is confident Selby-Rickit "will add significantly to our environment".
"He certainly brings depth and competition in a position where we believe legitimate height and Super Rugby level experience is highly advantageous and not easy to come by."
Selby-Rickit is the son of former All Black Hud Rickit who was also a part of the New Zealand Maori side and represented Waikato at provincial level from 1979-82.
His sisters Te Paea and Te Huinga Reo Selby-Rickit have also represented New Zealand at netball.
The Highlanders will not be left short following his departure. They will lean on Josh Dickson and Pari Pari Parkinson to carry the load in the second row, while Otago lock Fabian Holland will get more opportunities and Max Hicks made an impact last season.
