
| Marcia Strassman | ... | Julie Kotter (92 episodes, 1975-1979) |
 | John Sylvester White | ... | Mr. Michael Woodman (92 episodes, 1975-1979) |

| Robert Hegyes | ... | Juan Epstein (92 episodes, 1975-1979) |
 | Lawrence Hilton-Jacobs | ... | Freddie 'Boom Boom' Washington (92 episodes, 1975-1979) |

| Ron Palillo | ... | Arnold Horshack (91 episodes, 1975-1979) |
 | Gabe Kaplan | ... | Gabe Kotter (79 episodes, 1975-1979) |

| John Travolta | ... | Vinnie Barbarino (78 episodes, 1975-1979) |
 | Stephen Shortridge | ... | Beau De Labarre (19 episodes, 1978-1979) |

| Helaine Lembeck | ... | Judy Borden (14 episodes, 1975-1978) |
 | Vernee Watson-Johnson | ... | Vernajean Williams (14 episodes, 1975-1977) |

| Charles Fleischer | ... | Carvelli (12 episodes, 1976-1979) |
 | Bob Harcum | ... | Murray (10 episodes, 1976-1979) |
 | Melonie Haller | ... | Angie Globagoski (8 episodes, 1978) |
 | Debralee Scott | ... | Rosalie 'Hotsy' Totsy (6 episodes, 1975-1978) |
 | Irene Arranga | ... | Mary Johnson (6 episodes, 1978-1979) |
 | Dennis Bowen | ... | Todd Ludlow (5 episodes, 1975-1977) |
 | Ernest Harada | ... | Mr. Jan (3 episodes, 1977-1978) |
 | Ellen Travolta | ... | Mrs. Horshack-O'Hara (3 episodes, 1977) |

| Linda McCullough | ... | Sally (3 episodes, 1978-1979) |
 | Denise Galik | ... | Paula Holtzgang (2 episodes, 1977) |
 | Amy Johnston | ... | Cassy (2 episodes, 1977) |
 | Martin Garner | ... | Lou (2 episodes, 1977) |
 | Sally Hightower | ... | Laura Stevens (2 episodes, 1978) |
 | Sam Weisman | ... | Peter Charnoff (2 episodes, 1978) |
 | Jane Dulo | ... | Nurse Bonnie (2 episodes, 1978-1979) |
 | Susan Lanier | ... | Bambi (2 episodes, 1975-1976) |
 | Georganne LaPiere | ... | Kelly Woodman (2 episodes, 1979) |

| Della Reese | ... | Mrs. Tremaine (2 episodes, 1979) |
|
| Earl Barret | .... | executive story consultant / executive script consultant (23 episodes, 1978-1979) |
| Bill Daly | .... | production clerk (23 episodes, 1978-1979) |
| Eric Cohen | .... | script supervisor / creative consultant / ... (13 episodes, 1975-1978) |
| Jewel Jaffe | .... | story editor / executive script consultant (12 episodes, 1975-1977) |
| Diane Katz | .... | assistant to producer (12 episodes, 1975-1977) |
| Jerry Rannow | .... | story editor / executive script consultant (12 episodes, 1975-1977) |
| Mei Ling Moore | .... | production assistant (12 episodes, 1975) |
| Sandy Carrillo | .... | administrative assistant (11 episodes, 1975) |
| Jim Cox | .... | stage manager (11 episodes, 1975) |
| Moki de Marco | .... | production assistant (11 episodes, 1975) |
| Linda Robertson | .... | production assistant (11 episodes, 1975) |
| Maxine Surks | .... | production assistant (11 episodes, 1975) |
| Christopher Cookson | .... | engineering supervisor (10 episodes, 1975-1976) |
| Karl Messerschmidt | .... | technical director (9 episodes, 1975) |
| Paul Miller | .... | stage manager (9 episodes, 1975) |
| George Yanok | .... | script consultant (7 episodes, 1975) |
| Sandy Dvore | .... | komack logo (5 episodes, 1975) |
| Peter Meyerson | .... | executive script consultant (4 episodes, 1975) |
| Susan Jenkins | .... | video tape editor (3 episodes, 1975) |
| Stephen McKeown | .... | video tape editor (3 episodes, 1975) |
| Giovanna Nigro | .... | stage manager (2 episodes, 1975) |
|
| James Woodworth | .... | stage manager (unknown episodes) |
| |