Alanna Ubach
Katherine 'Cutter' Sterns (voice) (31 eps)
Lucas Neff
Duncan P. Anderson (voice) (22 eps)
Billy Crystal
Mike Wazowski (voice) (20 eps)
John Goodman
James P. 'Sulley' Sullivan (voice) (20 eps)
Ben Feldman
Tylor Tuskmon (voice) (20 eps)
Mindy Kaling
Val Little (voice) (20 eps)
Henry Winkler
Fritz (voice) (20 eps)
Stephen Stanton
Smitty / Needleman / Sanderson (voice) (18 eps)
Christopher Swindle
Phlegm (voice) (15 eps)
Bob Peterson
Roze (voice) (12 eps)
Dee Bradley Baker
Banana Bread (voice) (10 eps)
Romi Dames
Additional Monsters (voice) (10 eps)
Roberts Gannaway
Roto (voice) (9 eps)
Bonnie Hunt
Ms. Flint (voice) (9 eps)
Jennifer Tilly
Celia Mae (voice) (8 eps)
John Ratzenberger
Bernard (voice) (8 eps)
Michaela Dietz
Additional Monsters (voice) (7 eps)
Nathan Fillion
Johnny (voice) (6 eps)
Carlos Alazraqui
Additional Monsters (voice) (6 eps)
Rhys Darby
Roger Rogers (voice) (6 eps)
Aisha Tyler
Millie (voice) (5 eps)
Curtis Armstrong
Mr. Crummyham (voice) (4 eps)
Jenifer Lewis
Grandma Tuskmon (voice) (4 eps)
Bobby Moynihan
Chet (voice) (4 eps)
Max Mittelman
Restaurant Patrons (voice) (4 eps)
Ali Wong
Jill (voice) (3 eps)
Joe Lo Truglio
Jack (voice) (3 eps)
Roxana Ortega
Celia Mae (voice) (3 eps)
Aubrey Plaza
Claire (voice) (3 eps)
Sander Argabrite
J.J. (voice) (3 eps)
Nohely Quiroz
FearCo. Receptionist (voice) (3 eps)
Alfred Molina
Professor Knight (voice) (2 eps)
Dave Wittenberg
Additional Monsters (voice) (2 eps)
Gabriel Iglesias
Gary (voice) (2 eps)
Alan Kim
Ben (voice) (2 eps)
Julia Butters
Lorelei (voice) (2 eps)
Kurtwood Smith
Alistair Clawbottom (voice) (2 eps)
Natalie Lashkari
Monster Kids (voice) (2 eps)
Emily Peterson
Fear Co. Narrator / Fancy Monsters (voice) (2 eps)
Paula Pell
Sunny (voice) (2 eps)
Corey Burton
C.R.E.E.P. WOrker / Sloppy (voice) (2 eps)
Richard Ayoade
Declan (voice) (2 eps)
Janelle James
Joy (voice) (2 eps)
Jennifer Coolidge
Marilyn (voice) (2 eps)
Ferrell Barron
Additional Monsters (voice) (1 eps)
Bob Uecker
Bob Yucker (voice) (1 eps)
John Michael Higgins
Argus Blinks (voice) (1 eps)
Hadley Gannaway
Thalia (voice) (1 eps)
Devin Bright
Marcus (voice) (1 eps)
Cooper J. Friedman
Alexander (voice) (1 eps)
Lucian Perez
Oscar (voice) (1 eps)
Isabella Abiera
Gurty (voice) (1 eps)
Kimberly Brooks
Additional Monsters (voice) (1 eps)
Danny Pudi
Evan (voice) (1 eps)
Danny Trejo
Terry (voice) (1 eps)
Cody Rigsby
Spin-Energy Instructor Monster (voice) (1 eps)
Ryan McPartlin
Bully Monster 1 / Mr. April (voice) (1 eps)
Stevie Wermers-Skelton
Scream Con Mascot / Bully Monster 2 (voice) (1 eps)
Kevin Deters
Janitor (voice) (1 eps)
Alan Tudyk
Pierre / Michel / Maître d' (voice) (1 eps)
Rania Sharkawy
Avani (voice) (1 eps)
Dan Molina
Ethan (voice) (1 eps)
Aubrey Matalon
Neighbor Monsters (voice) (1 eps)
Evan Ridpath
Tiny Monster (voice) (1 eps)
Jimmy Tatro
Skyler (voice) (1 eps)
Ethan Sandler
Stubby Lizzardo (voice) (1 eps)
Bowen Yang
Carter (voice) (1 eps)