Jason Lee David Seville David Cross Ian Jenny Slate Zoe Justin Long Alvin (voice) Matthew Gray Gubler Simon (voice) Jesse McCartney Theodore (voice) Amy Poehler Eleanor (voice) Anna Faris Jeanette (voice) Christina Applegate Brittany (voice) Alan Tudyk Simone (voice) Michael P. Northey Hawaiian Shirt Guy Sophia Aguiar Club Woman #1 Lauren Gottlieb Club Woman #2 Andy Buckley Captain Correlli Luisa d'Oliveira Tessa Tucker Albrizzi Tucker / Kite Kid Nelson Wong Casino Guy Ian Harmon Monster Phyllis Smith Flight Attendant Ross Bagdasarian, Jr. Alvin (singing voice) (uncredited) Janice Karman Theodore / The Chipettes (singing voice) (uncredited) Steve Vining Simon (singing voice) (uncredited)