Steve Carell

David Sheff

Timothée Chalamet

Nic Sheff

Maura Tierney

Karen Barbour

Amy Ryan

Vicki Sheff

Christian Convery

Jasper Sheff

Oakley Bull

Daisy Sheff

Kaitlyn Dever

Lauren

Stefanie Scott

Julia

Julian Works

Gack

Jack Dylan Grazer

12-Year-Old Nic Sheff

Zachary Rifkin

8-Year-Old Nic Sheff

Kue Lawrence

5-Year-Old Nic Sheff

Timothy Hutton

Dr. Brown

Amy Forsyth

Diane

Andre Royo

Spencer

Ricky Low

Destiny

LisaGay Hamilton

Rose

Carlton Wilborn

Vince

Amy Aquino

Annie Goldblum

Marypat Farrell

Julia's Mother

Brandon James Cienfuegos

Kid

Cheska Corona

Kid

Mandeiya Flory

Kid

Martha T. Newman

Flight Attendant

Minerva García

Nurse @ Bellevue

Nikki Snipper

Airline Attendant

Anastasia Leddick

Speaker @ 12 Step Meeting

Edward Fletcher

Minister

Justin Townes Earle

Wedding Guest

Seann Gallagher

Father @ Graduation

Brooklin Thacher

Principal @ Graduation

Sasha Kelly Jackson

EMT

Tom Beyer

Meeting Leader

David Mendenhall

Rocker (uncredited)