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)
Rae Sunshine Lee
Concert Attendee (uncredited)
Meghan Noone
Alvin's Fan (uncredited)
Chris Rossi
Dancer (uncredited)
Jameel Saleem
Band Roadie (uncredited)
Melanie Stephens
Dancing DJ (uncredited)
Gregg Lee
Concert Attendee (uncredited)