On screen
Cast
70 credited performers
Stephen Stanton
Smitty / Needleman (voice)
Alanna Ubach
Cutter / Rosie (voice)
Lucas Neff
Duncan / Father (voice)
Billy Crystal
Mike (voice)
Ben Feldman
Tylor (voice)
Mindy Kaling
Val (voice)
Henry Winkler
Fritz (voice)
John Goodman
Sulley (voice)
Christopher Swindle
Fungus / Phlegm / McLean / Additional Monsters (voice)
Bob Peterson
Roz / Bob Peterson (voice)
Dee Bradley Baker
Banana Bread / Chompy / Swamp Man / Angry Citizen (voice)
Romi Dames
Additional Monsters (voice)
Bobs Gannaway
Otis / Roto / Bobs (voice)
John Ratzenberger
Bernard (voice)
Bonnie Hunt
Ms. Flint (voice)
Rhys Darby
Roger Rogers (voice)
Jennifer Tilly
Celia Mae (voice)
Nathan Fillion
Johnny (voice)
Michaela Dietz
Snore (voice)
Carlos Alazraqui
Josh Rivera / Jebediah (voice)
Aisha Tyler
Millie (voice)
Bobby Moynihan
Chet (voice)
Max Mittelman
Scared Monster / Convention Monsters (voice)
Jenifer Lewis
Grandma Tuskmon (voice)
Ali Wong
Jill (voice)
Joe Lo Truglio
Jack (voice)
Roxana Ortega
Celia Mae (voice)
Nohely Quiroz
MNN Receptionist / MU Student (voice)
Curtis Armstrong
Mr. Crummyham (voice)
Alan Kim
Ben (voice)
Paula Pell
Sunny (voice)
Corey Burton
C.R.E.E.P. WOrker / Sloppy (voice)
Richard Ayoade
Declan (voice)
Janelle James
Joy (voice)
Aubrey Plaza
Claire (voice)
Julia Butters
Lorelei (voice)
Sander Argabrite
J.J. (voice)
Kimberly Brooks
Additional Monsters (voice)
Kurtwood Smith
Alistair Clawbottom (voice)
Jimmy Tatro
Skyler (voice)
Alan Tudyk
M.E.R.C. Official 1 / Alarmed Monster (voice)
Alfred Molina
Professor Knight (voice)
Dave Wittenberg
Additional Monsters (voice)
Gabriel Iglesias
Gary (voice)
Natalie Lashkari
Little Girl Monster (voice)
Emily Peterson
Fear Co. Narrator / Fancy Monsters (voice)
Jennifer Coolidge
Marilyn (voice)
Kevin Deters
DJ Slinky Stinkwell (voice)
Ethan Sandler
Stubby Lizzardo (voice)
Stevie Wermers-Skelton
Swamp Woman (voice)
Bowen Yang
Carter (voice)
Aubrey Matalon
Neighbor Monsters (voice)
Steve Buscemi
Randall (voice)
Ferrell Barron
Additional Monsters (voice)
Bob Uecker
Bob Yucker (voice)
John Michael Higgins
Argus Blinks (voice)
Hadley Gannaway
Thalia (voice)
Devin Bright
Marcus (voice)
Cooper J. Friedman
Alexander (voice)
Lucian Perez
Oscar (voice)
Isabella Abiera
Gurty (voice)
Danny Pudi
Evan (voice)
Danny Trejo
Terry (voice)
Cody Rigsby
Spin-Energy Instructor Monster (voice)
Ryan McPartlin
Bully Monster 1 / Mr. April (voice)
Rania Sharkawy
Avani (voice)
Dan Molina
Ethan (voice)
Evan Ridpath
Tiny Monster (voice)
Tessa Rozanski
Hilary / Sweet Kid (voice)
Sam Deters
Not Valet Monster (voice)