Miles Bakshi

Tim (voice)

Alec Baldwin

Boss Baby (voice)

Jimmy Kimmel

Dad (voice)

Lisa Kudrow

Mom (voice)

Steve Buscemi

Francis Francis (voice)

Tobey Maguire

Adult Tim / Narrator (voice)

James McGrath

Wizzie / Elvis Impersonator (voice)

Conrad Vernon

Eugene (voice)

ViviAnn Yee

Staci (voice)

Eric Bell Jr.

Triplets (voice)

David Soren

Jimbo (voice)

Edie Mirman

Big Boss Baby (voice)

James Ryan

Story Bear (voice)

Walt Dohrn

Photographer (voice)

Jules Winter

Crying Boy / Little Boy / Boy (voice)