Infinitely Polar Bear

Mark Ruffalo

Cameron

Zoe Saldaña

Maggie

Imogene Wolodarsky

Amelia Stuart

Ashley Aufderheide

Faith Stuart

Wallace Wolodarsky

Peter

Keir Dullea

Murray Stuart

Beth Dixon

Pauline Stuart

Georgia Lyman

Becca

William Xifaras

Bus Driver

Mary O'Rourke

Receptionist

Chris Papavasiliou

Mr. Fabrini

Liam McNeill

Young Man 1

Mark S. Cartier

Maitre d'

Alicia Love

Carol

Manoah Angelo

Thurgood

Nekhebet Kum Juch

Kim

Muriel Gould

Gaga

Paul Elias

Dick

Uatchet Jin Juch

Ali

Wendy Forbes

Maid

Tod Randolph

Ruth-Ann

Patrick Shea

Business Man 1

Brianne Siddall

Additional Voices #3 (voice)

Christopher Alan

Bar Fly (uncredited)

Christopher S. Porter

Bar Patron (uncredited)

George J. Vezina

Joe - Institution Patient (uncredited)

Michael Underhill

Young Businessman (uncredited)

Mike Jablon

Unfriendly Houseguest (uncredited)

David Weindel

Homeless Friend (uncredited)

Scout Lyons

School girl

Grant George

Additional Voices #1 (voice)