Elliot Page
as Juno MacGuff

Michael Cera
as Paulie Bleeker

Jennifer Garner
as Vanessa Loring

Jason Bateman
as Mark Loring

J.K. Simmons
as Mac MacGuff

Allison Janney
as Bren MacGuff

Olivia Thirlby
as Leah

Eileen Pedde
as Gerta Rauss

Rainn Wilson
as Rollo

Daniel Clark
as Steve Rendazo

Darla Fay
as Bleeker's Mom

Aman Johal
as Vijay

Valerie Tian
as Su-Chin

Emily Perkins
as Punk Receptionist

Kaaren de Zilva
as Ultrasound Technician

Steven Christopher Parker
as Guy Lab Partner

Candice King
as Amanda, Girl Lab Partner

Sierra Pitkin
as Liberty Bell

Cut Chemist
as Chemistry Teacher

Eve Harlow
as Tough Girl

Kirsten Alter
as Nurse

Emily Tennant
as Pretty-to-Goth Girl

Ashley Whillans
as Katrina De Voort

Jeff Witzke
as Track Announcer

Colin McSween
as Keith

Peggy Logan
as Sex Ed Teacher

Cameron Bright
as RPG Nerd

Joy Galmut
as Delivery Room Doctor

Wendy Russell
as Vanessa's Friend #1

Robyn Ross
as Vanessa's Friend #2