The club captain has scored 79 goals and contributed 67 assists in his 234 appearances for the club.
Fernandes, who has already won three Sir Matt Busby Player of the Year awards, has created more chances than any other Premier League player since he joined United in January 2020.
Bruno Fernandes said: “Everybody knows the passion I have for Manchester United. I understand the responsibility and significance of wearing this shirt, and the levels of dedication and desire required to represent this incredible club.
“I have had so many special moments here already; hearing my name sung from the Stretford End, scoring a hat-trick against Leeds, leading the team out at Old Trafford on European nights and lifting trophies at Wembley.