Bill Skarsgård
Pennywise

James McAvoy
Bill Denbrough

Jessica Chastain
Beverly Marsh

Bill Hader
Richie Tozier

Isaiah Mustafa
Mike Hanlon

Jay Ryan
Ben Hanscom

James Ransone
Eddie Kaspbrak

Andy Bean
Stanley Uris

Teach Grant
Henry Bowers

Jaeden Martell
Young Bill Denbrough

Sophia Lillis
Young Beverly Marsh

Finn Wolfhard
Young Richie Tozier

Chosen Jacobs
Young Mike Hanlon

Wyatt Oleff
Young Stanley Uris

Jeremy Ray Taylor
Young Ben Hanscom

Jack Dylan Grazer
Young Eddie Kaspbrak

Nicholas Hamilton
Young Henry Bowers

Molly Atkinson
Myra / Sonia Kaspbrak

Luke Roessler
Dean

Joan Gregson
Mrs. Kersh

Jackson Robert Scott
Dead Georgie

Javier Botet
Hobo / The Witch

Xavier Dolan
Adrian Mellon

Taylor Frey
Don Hagarty

Stephen Bogaert
Alvin Marsh

Stephen King
Shopkeeper

Peter Bogdanovich
Peter

Will Beinbrink
Tom

Jess Weixler
Audra Phillips

Martha Girvin
Patty

Ryan Kiera Armstrong
Victoria Fuller

Jake Weary
Webby

Katie Lunman
Chris Unwin

Kelly Van der Burg
Victoria's Mom

Jason Fuchs
Richie's Manager

Joe Bostick
Mr. Keene

Megan Charpentier
Young Gretta

Juno Rinaldi
Gretta

Neil Crone
Chief Borton

Ry Prior
Connor

Owen Teague
Dead Hockstetter

Jake Sim
Belch Huggins

Logan Thompson
Victor Criss

Connor Smith
Carny

Amanda Zhou
Waitress

Rob Ramsay
Meaner Nurse

John Connon
John Koontz (Juniper Hill Security)

Doug MacLeod
Head Honcho

Brandon Crane
Big Guy

Erik Junnola
Scuzzah

Josh Madryga
Scuzzah

Kiley May
Shokopiwah Woman

Lisa Cromarty
Shokopiwah Woman

Kevin Allan Hess
Shokopiwah Man

Stephen R. Hart
Shokopiwah Man

Billy Merasty
Shokopiwah Man

Sladen Peltier
Shokopiwah Young Boy

Ari Cohen
Stanley's Dad

Alex Bird
Theatre P.A.

Brody Bover
Shouting Kid

Edie Inksetter
Shouting Kid's Mom

Martin Julien
Janitor

Sonia Maria Chirila
Fishtank Girl

Declan Prior
Bully

Marko Vujicic
Bully

Eric Woolfe
Nurse

Kate Corbett
Dean's Mom

Janet Porter
Richie's Mom

Anthony Ulc
The Butcher

Louise Stratten
Audra's Assistant

Carla Guerrier
Police Officer

Liam MacDonald
Dean's Friend

Thiago Dos Santos
Twitchy Man

Andy Muschietti
Pharmacy Customer (uncredited)