Speculation over Robertson's future has mounted since December amid reports of friction between senior players and All Blacks staff.
Robertson, who replaced Ian Foster after the 2023 World Cup, guided the All Blacks to 10 wins out of 13 tests in the 2025 season, but the former Canterbury Crusaders coach came under pressure following a first-ever away defeat to Argentina and a record 43-10 loss to South Africa in Wellington.
The All Blacks were also well-beaten by England at Twickenham in November, ending their hopes of completing a Grand Slam of wins against the Home Nations.
“The mid-point in the Rugby World Cup cycle is the right time to look at the All Blacks’ progress over the first two seasons. The team are set to play a significant 2026 schedule, and the tournament in 2027 remains the key goal," New Zealand Rugby (NZR) chairman David Kirk said in a statement.
“We’ve taken an extensive look at the team’s progress on and off the field and have subsequently had discussions with Scott on the way forward. Both NZR and Scott agree it is in the best interests of the team that he depart his role as Head Coach."
Robertson, who was contracted to the end of the 2027 World Cup in Australia, said he was "gutted" by the decision but had agreed to cut short his tenure after reflecting on feedback in the review.
"Coaching the All Blacks has been the honour of my life. I am incredibly proud of what this team has achieved and of the progress we have made," Robertson said in a separate statement.
"We have brought through a talented group of young players, strengthened the depth across the squad, and set solid foundations for the years ahead.
"Following the end of year review I have taken time to reflect on some of the feedback. My priority has always been the success of the All Blacks and, after discussions with New Zealand Rugby, I believe it is in the best interests of the team for me to step aside.
"I have therefore reached an agreement with New Zealand Rugby to end my contract early so a new coaching group has the time it needs to prepare and take the team into the next World Cup."
The governing body said a search for a replacement would commence immediately, with the All Blacks set to play their first Nations Championship tests in July.
Former Japan coach Jamie Joseph is seen as front-runner to replace Robertson who was unable to replicate his huge success at provincial level with the Crusaders at test level.