Garrett Hedlund admits that Tomorrowland‘s poor box office performance affected TRON 3‘s chances of happening.
While TRON 3 is unlikely to ever happen, Disney is working on a TRON reboot with Jared Leto in the title role.
A clear example of this is Joseph Kosinski’s TRON: Legacy, which released 28 years after Steven Lisberger’s TRON and takes place 27 years after the events of that first film.
A third film was finally confirmed in 2015, but Disney ended up canceling TRON 3 altogether that May.