The All Blacks and Crusaders midfielder will link up with Japanese club Kubota Spears after the tournament.
Crotty said today he was looking forward to a new challenge.
"I know I'll look back at the end of my career in New Zealand with really fond memories of the experiences I've had and what I've achieved alongside my good mates, but for now my focus is enjoying the season ahead and helping to lead this Crusaders side one last time in 2019.
"The All Blacks, Crusaders and Canterbury rugby have been such an important part of my life and I'm grateful for every opportunity I've had to represent my country, my province and my family over the years," Crotty said.
Crotty made his debut for Canterbury in 2008, and pulled on the Crusaders jersey the following year.
The 30-year-old currently has 142 Super Rugby caps to his name, and has been vice-captain of the sides that won consecutive Super Rugby titles in the 2017 and 2018 seasons.
He made his All Blacks debut against the Wallabies in Sydney in 2013, and has earned 44 caps in the black jersey to date, scoring nine tries and being a consistent and solid performer in the All Blacks midfield.
Crusaders head coach Scott Robertson paid tribute to Crotty.
"Crotts is an outstanding leader in our backline and has delivered consistent performances in our midfield for more than a decade. We're fortunate to have one more season with him in 2019 and an opportunity to tick off more important milestones before he departs for Japan," Robertson said.
All Blacks coach Steve Hansen said Crotty would leave with New Zealand Rugby's best wishes.
"Crotts has been one of the mainstays of our midfield for many years and is a world-class footballer. He's a very physical, well-balanced rugby player, an outstanding communicator and decision-maker, who runs great lines and has a great pass.
"He's been a real asset to the All Blacks, Crusaders and Canterbury and will leave New Zealand rugby at the end of the season with our very best wishes."
Crotty joins a list of All Blacks heading overseas after the World Cup, including Kieran Read, Ben Smith, Owen Franks, Liam Squire, Jackson Hemopo, Luke Whitelock, Nehe Milner-Skudder and Jordan Taufua.