- Dan Castellaneta: Homer Simpson, Grampa Simpson, Barney Gumble, Krusty the Clown, Mayor Joe Quimby, Groundskeeper Willie, Sideshow Mel and Hans Moleman and others.
- Julie Kavner: Marge Simpson, Patty Bouvier, Selma Bouvier, Jacqueline Bouvier
- Nancy Cartwright: Bart Simpson, Nelson Muntz, Todd Flanders, Ralph Wiggum, Kearney, Maggie Simpson1 and others.
- Yeardley Smith: Lisa Simpson
- Hank Azaria2: Moe Szyslak, Clancy Wiggum, Apu Nahasapeemapetilon, Professor Frink, Comic Book Guy, Bumblebee Man, and others.
- Harry Shearer: Mr. Burns, Waylon Smithers, Ned Flanders, Principal Skinner, Reverend Lovejoy, Lenny Leonard and others.
1 Generally, Nancy Cartwright voices Maggie Simpson's sound effects such as squeaks, giggles, burps etc. However, other people have occasionally voiced her as well: Yeardley Smith provided her squeaks early on in the series, Elizabeth Taylor guest voiced as her in "Lisa's First Word", James Earl Jones voiced her in "Treehouse of Horror V", using his Darth Vader voice, Harry Shearer voiced her in "Treehouse of Horror IX", using his Kang voice and Jodie Foster voiced an adult Maggie in "Four Great Women and a Manicure".
2 Azaria did not become a main cast member until Season 2, before then he was credited as either Also Starring or Guest Star.
Also Starring Edit
- Pamela Hayden: Milhouse Van Houten, Rod Flanders, Jimbo Jones, Sarah Wiggum, Janey Powell and many others. (Season 1-present)
- Tress MacNeille: Agnes Skinner, Dolph Starbeam, Crazy Cat Lady, Cookie Kwan, Brandine Spuckler, many others. (Season 1-present)
- Maggie Roswell: Helen Lovejoy, Maude Flanders, Elizabeth Hoover, Luann Van Houten, Mary Bailey, many others. (Season 1-11, 13-present)
- Russi Taylor: Martin Prince, Sherri and Terri, Üter. (Season 1-present)
- Karl Wiedergott: Legs and additional voices. (Season 10-present)
- Christopher Collins: Original voice of Mr. Burns. (Season 1)
- Doris Grau: Lunchlady Doris (Season 2-7, 9)
- Jo Ann Harris: Additional voices. (Season 1-4)
- Marcia Mitzman Gaven: Temporarily replacing Maggie Roswell. (Season 11-14)
Recurring Special Guest Voices Edit
Including cast with 5+ appearances. See List of guest stars for a complete list of characters.
- Albert Brooks1: Cowboy Bob, Jacques, Brad Goodman, Hank Scorpio, Tab Spangler. (Season 1, 5, 8, 16, The Simpsons Movie)
- Kelsey Grammer: Sideshow Bob. (Season 1, 3, 5-8, 12, 14, 17, 19-21)
- Jane Kaczmarek: Judge Constance Harm (Season 13-16, 18, 21)
- Maurice LaMarche: Additional voices. (Season 6, 16-21)
- Jon Lovitz: Artie Ziff, Professor Lombardo, Aristotle Amadopolis, Jay Sherman, Llewellyn Sinclair. (Season 1-4, 6, 8, 13, 15, 18, 24)
- Joe Mantegna: Fat Tony (Season 3, 6-8, 10-14, 16-18, 20-22)
- Greg Berg: Additional voices (Season 2, 7-8)
- Phil Hartman: Troy McClure, Lionel Hutz, Lyle Lanley, many others. (Season 2-10)
- Jan Hooks: Manjula Nahasapeemapetilon (Season 9-14)
- Frank Welker2: Santa's Little Helper, other animals. (Season 2-3, 5-8, 11-13)
- Marcia Wallace: Edna Krabappel (Season 1-25)
- James Earl Jones: Maggie Simpson (Season 1-13)
- Ron Taylor: Bleeding Gums Murphy (Season 1-5)
- Julie Kavner: Nelson Muntz, Julie Chambers (Season 1-13)
1 Credited as "A. Brooks". During season 1, he was credited as "Also Starring".
2 Credited both as "Special Guest Voice" and "Also Starring".
- David Cohen
- Al Jean
- Ian Maxtone-Graham
- George Meyer
- Bill Oakley
- Conan O'Brien
- Mike Reiss
- John Swartzwelder
- Jon Vitti
- Josh Weinstein
- John Frink P.S This writer is based on Professor John Frink (The Scienctist)
- Matt Groening