Billy West performs the voices of Philip J. Fry, Professor Farnsworth, Doctor Zoidberg, Zapp Brannigan and many other incidental characters. West auditioned for “just about every part”, landing the roles of the Professor and Doctor Zoidberg. Although West read for Fry, his friend Charlie Schlatter was given the role of Fry.Due to a casting change, West was called back to audition again and was promptly given the role. West claims that the voice of Fry is deliberately modeled on his own, so as to make it difficult for another person to replicate the voice. Doctor Zoidberg’s voice is based on Lou Jacobi and George Jessel. The character of Zapp Brannigan was originally created and intended to be performed by Phil Hartman.Hartman insisted on auditioning for the role, and “just nailed it” according to Groening. Due to Hartman’s death, West was subsequently given the role. West states that his version of Zapp Brannigan is an imitation of Hartman and also “modeled after a couple of big dumb announcers I knew.”
Tom voices Amy Wong.
MacNeille voices Mom and various other characters.
LaMarche voices Kif Kroker and several supporting characters. LaMarche won the Emmy Award for Outstanding Voice-Over Performance in 2011 for his performances as Lrrr and Orson Welles in the episode “Lrrreconcilable Ndndifferences.”
DiMaggio performs the voice of the robot Bender Bending Rodríguez and other, more minor, characters. Bender was the most difficult character to cast, as the show’s creators had not decided what a robot should sound like. DiMaggio originally auditioned for the role of Professor Farnsworth, using the voice he uses to perform Bender, and also auditioned for Bender using a different voice. DiMaggio describes Bender’s voice as a combination of a sloppy drunk, Slim Pickens and a character his college friend created named “Charlie the sausage-lover.”
Sagal voices exclusively Leela, and is the only member of the main cast to voice only one character. The role of Leela was originally assigned to Nicole Sullivan. In an interview in June 2010, Sagal remarked that she did not know that another person was to originally voice Leela until many years after the show first began; going on to state that she is still unaware who the original voice actor even is.
LaMarr voices Hermes Conrad