Johnny Galecki
Leonard Hofstadter (24 eps)
Jim Parsons
Sheldon Cooper (24 eps)
Kaley Cuoco
Penny (24 eps)
Simon Helberg
Howard Wolowitz (24 eps)
Kunal Nayyar
Rajesh Koothrappali (24 eps)
Melissa Rauch
Bernadette Rostenkowski (24 eps)
Mayim Bialik
Amy Farrah Fowler (24 eps)
Kevin Sussman
Stuart Bloom (13 eps)
Swati Kapila
Ruchi (3 eps)
Wil Wheaton
Wil Wheaton (3 eps)
Brian Posehn
Bert Kibbler (3 eps)
Jerry O'Connell
Georgie Cooper (2 eps)
Pamela Adlon
Halley Wolowitz (voice) (2 eps)
Lauren Lapkus
Denise (2 eps)
Christine Baranski
Beverly Hofstadter (2 eps)
Dean Norris
Richard Williams (1 eps)
Susan Chuang
Dr. Harris (1 eps)
Riki Lindhome
Ramona Nowitzki (1 eps)
George Wyner
Dr. Zane (1 eps)
Carol Ann Susi
Debbie Wolowitz (voice) (1 eps)
Ira Flatow
Ira Flatow (1 eps)
Beth Behrs
Nell (1 eps)
Walton Goggins
Oliver (1 eps)
Dana L. Wilson
Dr. Sanders (1 eps)
Marissa Cuevas
Danielle (1 eps)
Michael Patrick McGill
Police Officer (1 eps)
Eric Normington
Man (1 eps)
Brooke Baumer
Denise (1 eps)
Elka Rodriguez
Rose Lady (1 eps)
Nicole J. Butler
Clerk (1 eps)
Bill Gates
Bill Gates (1 eps)
Mark Hamill
Mark Hamill (1 eps)
Courtney Henggeler
Missy Cooper (1 eps)
Kathy Bates
Mrs. Fowler (1 eps)
Teller
Larry Fowler (1 eps)
Regina King
Janine Davis (1 eps)
Michelle Arthur
Mrs. Petrescu (1 eps)
Parvesh Cheena
Marcus (1 eps)
Bob Stephenson
Wendell (1 eps)
Megan McGown
Cynthia (1 eps)
Neil Gaiman
Neil Gaiman (1 eps)
Patrick Daniel
Grant (1 eps)
Peter MacNicol
Robert Wolcott (1 eps)
James Maslow
Bartender (1 eps)
Edward James Gage
Nicholas (1 eps)
Ed Lieberman
Lecturer (voice) (1 eps)
Joshua Malina
President Siebert (1 eps)
Mark Berry
Pit Boss (1 eps)
Evan Charest
Croupier (1 eps)
D'Kia Anderson
Hostess (1 eps)
Seth Coltan
Earl (1 eps)
Ellie Reed
Jenna (1 eps)
Bob Newhart
Arthur Jeffries (1 eps)
Cat Hammons
Nurse (1 eps)
Joey Rich
Man (1 eps)
Jeffrey Cade Ross Brown
Toby (1 eps)
Caleb Pierce
Jess (1 eps)
Rachna Khatau
Kathleen (1 eps)
Laura Cerón
Marta (1 eps)
Eileen Galindo
Letty (1 eps)
Lynn Andrews
Margaret (1 eps)
Brian Thomas Smith
Zack Johnson (1 eps)
Stephen Hawking
Stephen Hawking (1 eps)
Efrain Gomez
Employee (1 eps)