Obsada i filmowcy

Jim Carrey

Horton

Steve Carell

Mayor

Carol Burnett

Kangaroo

Will Arnett

Vlad

Seth Rogen

Morton

Dan Fogler

Councilman / Yummo Wickersham

Isla Fisher

Dr. Mary Lou Larue

Jonah Hill

Tommy

Amy Poehler

Sally O'Malley

Jaime Pressly

Mrs. Quilligan

Charles Osgood

Narrator

Josh Flitter

Rudy

Niecy Nash-Betts

Miss Yelp

Jesse McCartney

JoJo

Shelby Adamowsky

Hedy / Hooly

Jack Angel

Old Time Who

Caitlin Rose Anderson

Helen

Emily Anderson

Heather

Jan Rabson

Town Cryer

John Cygan

Who