Jason Lee

Dave

David Cross

Ian

Cameron Richardson

Claire

Jane Lynch

Gail

Justin Long

Alvin (voice)

Matthew Gray Gubler

Simon (voice)

Jesse McCartney

Theodore (voice)

Allison Karman

Female Intern 1

Tiara Parker

Female Intern 2

Kira Verrastro

Female Intern 3

Veronica Alicino

Amy

Beth Riesgraf

Mother in Store

Adriane Lenox

Vet

Don Tiffany

Engineer

Lorne Green

Director

Kevin Symons

Ted

Frank Maharajh

Barry

Greg 'G-Spot' Siebel

Photographer

Oliver Muirhead

Butler

Jayden Lund

Security Guard

Erin Chambers

Press Coordinator

Jillian Warry Barberie

Jillian Reynolds

Chris Classic

DJ

Adam Riancho

French Doll (voice)

Axel Alba

Spanish Doll (voice)

Rosero McCoy

Choreographer

Alexis Boyd

Dancer

Criscilla Anderson

Dancer

Kevin Fisher

Dancer

Kyndra Reevey

Dancer

Tucker Barkley

Dancer

Celestina Aladekoba

Dancer

Laura Edwards

Dancer

Christopher Scott

Dancer

Miss Prissy

Dancer

Bryan Gaw

Dancer

Michelle Maniscalco

Dancer

Nick Drago

Dancer

Melanie Lewis

Dancer

Natalie Cohen

Poolside Girl (uncredited)

Ross Bagdasarian, Jr.

Alvin (singing voice) (uncredited)

Janice Karman

Theodore (singing voice) (uncredited)

Lisa Mason Lee

Band Member (uncredited)

Meghan Noone

Alvin's Fan (uncredited)

Chris Rossi

Dancer (uncredited)

Jameel Saleem

Band Roadie (uncredited)

Melanie Stephens

Dancing DJ (uncredited)