| Name (Sort) | Character (Sort) | |
| •Kate Walsh | played | Dr. Addison Forbes Montgomery (78Eps.) |
| •Taye Diggs | played | Dr. Sam Bennett (78Eps.) |
| •Paul Adelstein | played | Dr. Cooper Freedman (78Eps.) |
| •Tim Daly | played | Dr. Pete Wilder (S01-S05) (78Eps.) |
| •Kadee Strickland | played | Dr. Charlotte King (78Eps.) |
| •Amy Brenneman | played | Dr. Violet Turner (78Eps.) |
| •Brian Benben | played | Dr. Sheldon Wallace (S02-; previously recurring) (22Eps.) |
| •Caterina Scorsone | played | Dr. Amelia Shepherd (S04-; previously recurring) (21Eps.) |
| •Benjamin Bratt | played | Dr. Jake Reilly (S05-) (29Eps.) |
| •Audra McDonald | played | Dr. Naomi Bennett (S01-S04) (48Eps.) |
| •Chris Lowell (1) | played | William "Dell" Parker (S01-S03) (35Eps.) |
| •Griffin Gluck | played | Mason Warner (S05 (Episode16) - ; previously recurring) (5Eps.) |