Director
Jimmy Hayward
DIRECTOR
Steve Martino
Stars (in credits order)
Jim Carrey
Hortonvoice
Steve Carell
Mayorvoice
Carol Burnett
Kangaroovoice
Will Arnett
Vladvoice
Seth Rogen
Mortonvoice
Dan Fogler
Councilmanvoice
Isla Fisher
Dr. Mary Lou Laruevoice
Jonah Hill
Tommyvoice
Amy Poehler
Sally O'Malleyvoice
Jaime Pressly
Mrs. Quilliganvoice
Charles Osgood
Narratorvoice
Josh Flitter
Rudyvoice
Niecy Nash
Miss Yelpvoice
Jesse McCartney
JoJovoice
Jack Angel
Old Time Whovoice
Jan Rabson
Town Cryervoice
John Cygan
Whovoice
Jess Harnell
Another Whovoice
Debi Derryberry
Who Momvoice
Samantha Droke
Hildyvoice
Karen Disher
Who Kidvoice
Marshall Efron
Wickersham Guard 1voice
Bill Farmer
Willie Bearvoice
Heather Goldenhersh
Who Girlvoice
Selena Gomez
Helgavoice
Obnoxious Whovoice
Joey King
Katievoice
Laraine Newman
Glummox Momvoice
Colleen O'Shaughnessey
Angelavoice
Laura Ortiz
Jessicavoice
Joe Pasquale
The Dentistvoice
Isabella Acres
Additional Voicesvoice
Bob Bergen
Jeff Biancalana
Madison Davenport
Teresa Ganzel
Sherry Lynn
Additional Voicevoice
Danny Mann
Mona Marshall
Madison Pettis
Grace Rolek
Jennessa Rose
Ariel Winter
Kresimir Mikic
Hortonuncredited
Shelby Adamowsky
Hedyvoice
Jason Fricchione
Joevoice
Caitlin Rose Anderson
Helenvoice
Christina Martino
Heidivoice
Emily Anderson
Heathervoice
Tim Nordquist
Wickersham Guard 2voice
Connor Anderson
Who Child #1voice
Mickie McGowan
Ellie Martino
Hannavoice
Kathy Graves Toon