Jenny Slate Mrs. Wiggins (voice)
Zac Efron Ted Wiggins (voice)
Danny DeVito The Lorax (voice)
Taylor Swift Audrey (voice)
Stephen Tobolowsky Uncle Ubb (voice)
Rob Riggle Mr. Aloysius O'Hare (voice)
Ed Helms Once-ler (voice)
Danny Cooksey Brett / Chet (voice)
Betty White Grammy Norma (voice)
Ken Daurio Executive Producer, Screenplay
Jack Angel Additional Voices (voice)
Cinco Paul Executive Producer, Songs, Screenplay
Bill Farmer Additional Voices (voice)
Debi Derryberry Additional Voices (voice)
Chris Renaud Director, Forest Animals (voice)
Bob Bergen Additional Voices (voice)
John Powell Original Music Composer, Songs
Jess Harnell Additional Voices (voice)
Kyle Balda Co-Director
Danny Mann Additional Voices (voice)
Mona Marshall Additional Voices (voice)
Gary Rizzo Sound Re-Recording Mixer
Nasim Pedrad Once-ler's Mom (voice)
Chris Meledandri Producer
Jim Ward Additional Voices (voice)
Randy Thom Sound Designer, Sound Re-Recording Mixer, Supervising Sound Editor
Laraine Newman Additional Voices (voice)
Yarrow Cheney Production Design
Joel Swetow 1st Marketing Guy (voice)
Dr. Seuss Book
Dave B. Mitchell 1st Commercial Guy (voice)
Mickie McGowan Additional Voices (voice)
Dempsey Pappion 2nd Commercial Guy (voice)
John Cygan Additional Voices (voice)
Daniel Laurie ADR Supervisor, Dialogue Editor
Jan Rabson Additional Voices (voice)
Ken Schretzmann Editor
Michael Beattie 2nd Marketing Guy (voice)
Dennis Leonard Supervising Sound Editor
Eric Guillon Character Designer
Fabrice Joubert Animation
Fletcher Sheridan Cy (voice)
Sherry Lynn Additional Voices (voice)
Carter Goodrich Character Designer
Claire Dodgson Editor
Steven Liu Editor
Mitja Rabar Animation
Claira Nicole Titman Additional Voices (voice)
Audrey Geisel Executive Producer
Catherine Catie Lee Lighting Artist
Massimo Ruberto Music Supervisor
Elmarie Wendel Aunt Grizelda (voice)
Janet Healey Producer