Buddy

Cristin Milioti

Grace

Delaney Quinn

Freddy

Topher Grace

Ben

Keegan-Michael Key

Buddy the Unicorn (voice)

Michael Shannon

Willie (voice)

Patton Oswalt

Strappy (voice)

Clint Howard

George

Eric Bauza

Mr. Mailbox / Worry Well / Couchy / Trashy / Pee Flower (voice)

Sergey Zhuravsky

Buddy the Unicorn (suit)

Jonathan Yurco

Dark Buddy (suit)

Devon Hawkes Ludlow

Charlie the Train (voice)

Jimmica Collins

Betty Bunny (voice)

Madison Polan

Hannah

Bryson JonSteele

Derek

Seamus Flynn

Timothy

Bennie Taylor

Mailman Miles

Cedwan Hooks

Betty Bunny (suit)

Mark Aaron Buerkle

Therapist (Day Player)

Phuong Kubacki

Nurse Nancy

Luke Speakman

Josh

Tristan Borders

Oliver

Caleb Williams

Wade

Conner Stumm

Mailman Justin

Eric Salazar

Grilling Man