Logan Lerman

Charlie

Emma Watson

Sam

Ezra Miller

Patrick

Mae Whitman

Mary Elizabeth

Kate Walsh

Mother

Dylan McDermott

Father

Melanie Lynskey

Aunt Helen

Nina Dobrev

Candace

Johnny Simmons

Brad

Joan Cusack

Dr. Burton

Paul Rudd

Mr. Anderson

Nicholas Braun

Ponytail Derek

Reece Thompson

Craig

Patrick de Ledebur

Senior Bully

Brian Balzerini

Linebacker

Tom Kruszewski

Nose Tackle

Julia Garner

Susan

Tom Savini

Mr. Callahan

Emily Marie Callaway

Mean Freshman Girl

Chelsea Zhang

Shakespeare Girl

Jesse Scheirer

Freshman Boy

Justine Nicole Schaefer

Twin Girl #1

Julie Marie Schaefer

Twin Girl #2

Leo Miles Farmerie

7-Year-Old Charlie

Isabel Muschweck

9-Year-Old Candace

Adam Hagenbuch

Bob

Erin Wilhelmi

Alice

Jordan Paley

Rocky MC

Zane Holtz

Chris

Timothy Breslin

Policeman

Mark McClain Wilson

Emergency Room Policeman

Atticus Cain

Emergency Room Doctor

Stacy Chbosky

Young Mom

Dihlon McManne

Priest

Laurie Klatscher

School Principal

Landon Pigg

Peter

Jennifer Enskat

Sam's Mom

William L. Thomas

Patrick's Dad

Morgan Wolk

Candace's Friend

Joe Fishel

Father of Twin Girls (uncredited)