Zac Efron Ted Wiggins (voice)
Danny DeVito The Lorax (voice)
Taylor Swift Audrey (voice)
Jenny Slate Mrs. Wiggins (voice)
Ed Helms Once-ler (voice)
Bob Bergen Additional Voices (voice)
Dave B. Mitchell 1st Commercial Guy (voice)
Stephen Tobolowsky Uncle Ubb (voice)
Danny Cooksey Brett / Chet (voice)
Dr. Seuss Book
Rob Riggle Mr. Aloysius O'Hare (voice)
Mike Reiss Story Consultant
Laraine Newman Additional Voices (voice)
Bill Farmer Additional Voices (voice)
Betty White Grammy Norma (voice)
Nasim Pedrad Once-ler's Mom (voice)
Ken Daurio Executive Producer, Screenplay
Kyle Balda Co-Director
Jack Angel Additional Voices (voice)
Jess Harnell Additional Voices (voice)
Debi Derryberry Additional Voices (voice)
Daniel Chong Additional Storyboarding
Mickie McGowan Additional Voices (voice)
Randy Thom Sound Re-Recording Mixer, Supervising Sound Editor, Sound Designer
Chris Renaud Director, Forest Animals (voice)
Glenn McCoy Additional Storyboarding
Joel Swetow 1st Marketing Guy (voice)
Cinco Paul Executive Producer, Songs, Screenplay
Bruno Chauffard CG Supervisor
Eric Favela Additional Storyboarding
Gary Rizzo Sound Re-Recording Mixer
Julien Soret Supervising Animator
Dempsey Pappion 2nd Commercial Guy (voice)
Danny Mann Additional Voices (voice)
Jim Ward Additional Voices (voice)
Boris Jacq Production Manager
John Holmquist Additional Storyboarding
John Cygan Additional Voices (voice)
Mona Marshall Additional Voices (voice)
Dennis Leonard Supervising Sound Editor
Jan Rabson Additional Voices (voice)
Chris Meledandri Producer
Claire Dodgson Editor
Mark O'Hare Story Artist
Dennie Thorpe Foley Artist
Robert Taylor Associate Producer
Daniel Laurie ADR Supervisor, Dialogue Editor
John Powell Original Music Composer, Songs
Sherry Lynn Additional Voices (voice)
Fletcher Sheridan Cy (voice)
Jana Vance Foley Artist
Frank Rinella Foley Mixer
Fabrice Joubert Animation, Supervising Animator
Janet Healy Producer
Guy Bar'ely Story Artist
Eric Guillon Character Designer, Art Direction
Luke Dunn Gielmuda Foley Editor
Carter Goodrich Character Designer
Sue Fox Foley Editor
Elmarie Wendel Aunt Grizelda (voice)
Sean England Foley Artist
Audrey Geisel Executive Producer
Michael Beattie 2nd Marketing Guy (voice)
Nicolas Bauduin Supervising Animator
Laurent de la Chapelle Animation Supervisor
Yarrow Cheney Production Design, Character Designer
Trevor Jimenez Additional Storyboarding
Didier Ah-Koon Story Artist
Matt Flynn Story Artist
Mike Kim Story Artist
Ken Schretzmann Editor
Wilbert Plijnaar Story Artist