Bill Skarsgård as Pennywise

Jaeden Martell as Bill Denbrough

Sophia Lillis as Beverly Marsh

Jeremy Ray Taylor as Ben Hanscom

Finn Wolfhard as Richie Tozier

Jack Dylan Grazer as Eddie Kaspbrak

Chosen Jacobs as Mike Hanlon

Wyatt Oleff as Stanley Uris

Nicholas Hamilton as Henry Bowers

Jackson Robert Scott as Georgie Denbrough

Stephen Bogaert as Mr. Marsh

Stuart Hughes as Officer Bowers

Owen Teague as Patrick Hockstetter

Molly Atkinson as Sonia Kasprak

Jake Sim as Belch Huggins

Logan Thompson as Victor Criss

Katie Lunman as Betty Ripsom

Geoffrey Pounsett as Zach Denbrough

Pip Dwyer as Sharon Denbrough

Steven Williams as Leroy Hanlon

Elizabeth Saunders as Mrs. Starret

Megan Charpentier as Gretta

Joe Bostick as Mr. Keene

Ari Cohen as Rabbi Uris

Anthony Ulc as Joe the Butcher

Javier Botet as Hobo

Carter Musselman as Headless Boy

Tatum Lee as Judith

Edie Inksetter as Hostess

Martha Gibson as Old Woman

Kasie Rayner as Field Hockey Girl #1

Isabelle Nélisse as Girl in Bathroom

Jocelyn Mattka as Another Girl

Donald Tripe as Old Man in Car

Liz Gordon as Old Woman in Car

Paige Rosamond as Dead Girl #1

Neil Crone as Chief Borton

Sonia Gascón as Mrs. Ripsom

Janet Porter as Stanley's Mother

Memo Díaz Capt. as 4th of July Clown

Chantal Vachon as Girl in Magazine

Roberto Campanella as Organ Player Clown

Cyndy Day as Pharmacy Cashier (uncredited)

David Katzenberg as El Aparato (uncredited)

Bobby Leigh as Jonathan (uncredited)

Kate Moyer as Esther (uncredited)

Sherry Nelson as Woman on Street (uncredited)

Jimmy Star as Man in Car (uncredited)

Kelly Van der Burg as Abigail (uncredited)

James Magwood as Student (uncredited)