Zachary Gordon

Greg Heffley

Robert Capron

Rowley Jefferson

Steve Zahn

Frank J. Heffley

Devon Bostick

Rodrick Heffley

Rachael Harris

Susan Heffley

Chloë Grace Moretz

Angie Steadman

Laine MacNeil

Patty Farrell

Andrew McNee

Coach Malone

Connor Fielding

Manny Heffley

Owen Fielding

Manny Heffley

Karan Brar

Chirag Gupta

Grayson Russell

Fregley

Alex Ferris

Collin

Belita Moreno

Mrs. Norton

Rob LaBelle

Mr. Winsky

Nicholas Carey

Pete Hosey

Samuel Patrick Chu

Carter

Donnie MacNeil

Wade

Samantha Page

Shelley

Ava Hughes

Marley

Owen Best

Bryce Anderson

Cainan Wiebe

Quentin

Cole Heppell

Quentin's Sidekick

Harrison Houde

Darren Walsh

Severin Korfer

Dieter Muller

Jennifer Clement

Mrs. Flint

Karin Konoval

Mrs. Irvine

Raugi Yu

Vice Principal Roy

Kaye Capron

Rowley's Mom

Jake D. Smith

Archie Kelly

Talon Dunbar

Arthur

Naomi Dane

Cheese Girl

Willem Jacobson

Cheese Boy

Sean Bygrave

Coach Brewer

Maxine Miller

Elderly Woman

Taya Clyne

Granddaughter

Nathaniel Marten

Grown-Up Greg

Peter New

Grown-Up Quentin

Nikki Frazer

Lunch Girl #1

Greta Makena Gibson

Lunch Kid #2

Nathan Smith

Kindergarten Boy

Kinua McWatt

Kindergarten Girl

Dylan Bell

Kindergarten Greg

Madison Bell

Kindergarten Patty

Adom Osei

Marty Porter

Alf Humphreys

Mr. Jefferson

Brent Chapman

Mr. Parnell

Rylee Stiles

Preston

Ryan Grantham

Rodney James

Ethan Shankaruk

Snot Kid

Jesse Wheeler

Unpopular 80s Boy

Paul Hubbard

Brock Branigan

Brett Dier

80s Breakdancer

Brandon Barton

80s Jock Boy

Cindy Busby

80s Popular Girl

Alicia Takase Lui

Audition Kid

Jay Sidhu

Audition Kid

Tori Christianson

Audition Kid

Emerald Schreier

Audition Kid

Ben Mitchell

Audition Kid

Haris Cash

Audition Kid

Mariah Crudo

Audition Kid

Alistair Abell

Male Reporter (voice)

Tara McGuire

Female Reporter (voice)

Aidan Gebert

Löded Diper

Cameron Krpan

Löded Diper

Paolo Tolfo

Löded Diper

Amy Esterle

Waitress (uncredited)

John Cygan

Parent (uncredited)