Bruce Willis as Ben Jordan

Michelle Pfeiffer as Katie Jordan

Rob Reiner as Stan Kogen

Colleen Rennison as Erin Jordan (at Ten)

Jake Sandvig as Josh Jordan (at Twelve)

Julie Hagerty as Liza

Rita Wilson as Rachel Kogen

Paul Reiser as Dave

Red Buttons as Arnie Jordan

Betty White as Lillian Jordan

Jayne Meadows as Dot

Tom Poston as Harry

Casey Boersma as Josh Jordan (at Two and a Half)

Dylan Boersma as Josh Jordan (at Three)

Ken Lerner as Dr. Rifkin

Albert Hague as Dr. Siegler

Michael Chapman as Waiter

Jessie Nelson as Realtor

Bill Kirchenbauer as Eddie Kirby

Yaping as Store Clerk