The club confirmed the decision in an official statement, bringing an end to Carrick's second spell at Old Trafford, which began in January. The former midfielder had initially taken charge on an interim basis and delivered a strong run of results, winning 12 of his 17 remaining Premier League matches in the 2025-26 campaign.
That sequence secured a third-placed finish, with United also recording the highest points tally in the league over that period. Carrick's achievements earned him a permanent appointment in May, but the club has now decided that a change of leadership is necessary after a difficult opening to the new season.
"After a disappointing start to the season, the club has come to the extremely difficult conclusion that a change is necessary in order to achieve our ambitions," United said.
The statement acknowledged the contribution Carrick made after returning to the club, while making clear that the board believes a different direction is required.
"Michael is, and always will be, a Manchester United legend. Just as he did as a player, he has conducted himself with the highest standards of dedication and professionalism throughout his time back with the club. His leadership and achievements last season will always be fondly remembered."
The 45-year-old's departure follows a dramatic collapse in league form. United had dropped into the relegation zone, sitting 18th ahead of the international break, after a run of results that left them facing the possibility of another season dominated by uncertainty.
The club's decision came after a review of the team's performances led by director of football Jason Wilcox, with chief executive Omar Berrada also involved in discussions over Carrick's position. The 4-4 draw against Aston Villa had been another opportunity for United to show signs of improvement, but the result was not enough to change the board's assessment.
Carrick had previously been given further time following a 3-0 home defeat against Bournemouth on 25 October. United subsequently beat Roma 3-2 in the Champions League and drew with Aston Villa, but their league position and overall performances continued to cause concern.
The club now intends to appoint a permanent successor as quickly as possible.
"The club intends to appoint a permanent successor as quickly as possible," the statement concluded.
Carrick leaves with his reputation as a former United player and his contribution to last season's recovery recognised by the club, but the disappointing start to the current campaign has ultimately proved decisive.