Zachary Levi Toby David Cross Ian Jason Lee Dave 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) Wendie Malick Dr. Rubin Anjelah Johnson-Reyes Julie Kathryn Joosten Aunt Jackie Kevin G. Schmidt Ryan Chris Warren Xander Bridgit Mendler Becca Aimee Carrero Emily Alexandra Shipp Valentina Gregg Binkley Emcee Jake Zyrus Charice Pempengco Bernard White Doctor Joy Osmanski Airline Rep Archie Hahn Agent Lanny Joon Paramedic Brando Eaton Jeremy Michael Bruno Honor Society Eric Bauza Digger the NASCAR Gopher (voice) Sean Astin Meerkat Manor Narrator (voice) Marty Dew Chipmunk Dancer Richy Jackson Chipmunk Dancer Mihran Kirakosian Chipmunk Dancer Thomasina Gross Chipette Dancer Rachele Brooke Smith Chipette Dancer Ryan Conferido Li'l Rosero Dancer Ryan Feng Li'l Rosero Dancer D-Trix Li'l Rosero Dancer Gee Alexander Simon Dance Double (uncredited) Casper Smart Dancer (uncredited)