 | Jack Lemmon als C.C. Baxter |
 | Shirley MacLaine als Fran Kubelik |
 | Fred MacMurray als Jeff D. Sheldrake |
 | Ray Walston als Joe Dobisch |
 | Jack Kruschen als Dr. Dreyfuss |
 | David Lewis als Al Kirkeby |
 | Hope Holiday als Mrs. Margie MacDougall |
 | Joan Shawlee als Sylvia |
 | Naomi Stevens als Mrs. Mildred Dreyfuss |
 | Johnny Seven als Karl Matuschka |
 | Joyce Jameson als The Blonde |
 | Willard Waterman als Mr. Vanderhoff |
 | David White als Mr. Eichelberger |
 | Edie Adams als Miss Olsen |
 | Dorothy Abbott als Office Worker (uncredited) |
 | Ralph Moratz als Office Worker (uncredited) |
 | Joe Palma als Office Maintenance Man (uncredited) |
 | Bill Baldwin als TV Movie Host (uncredited) |
| Benny Burt als Charlie - Bartender (uncredited) |
 | Lynn Cartwright als Elevator Supervisor with Clicker (uncredited) |
| Mason Curry als Bit Part (uncredited) |
 | David Macklin als Messenger (uncredited) |
 | Hal Smith als Man in Santa Claus Suit (uncredited) |
 | Paul Bradley als Office Worker (uncredited) |
 | Steve Carruthers als Restaurant Patron (uncredited) |
| Dick Cherney als Bar Patron (uncredited) |
 | Franklyn Farnum als Office Worker (uncredited) |
 | Herschel Graham als Restaurant Patron (uncredited) |
| Lars Hensen als Office Worker (uncredited) |
 | Eugene Jackson als Office Worker (uncredited) |
| Frances Weintraub Lax als Mrs. Lieberman (uncredited) |
| William Meader als Executive (uncredited) |
 | Monty O'Grady als Office Worker (uncredited) |
| Paul Power als Bar Patron (uncredited) |
| Tony Regan als Executive (uncredited) |
| Clark Ross als Restaurant Patron (uncredited) |
| Norman Stevans als Office Worker (uncredited) |
| Sid Troy als Williams (uncredited) |
| Billy Wilder | Producer |
| Adolph Deutsch | Original Music Composer |
| Joseph LaShelle | Director of Photography |
| Daniel Mandell | Editor |
| Alexandre Trauner | Art Direction |
| Edward G. Boyle | Set Decoration |
| Harry Ray | Makeup Artist |
| Allen K. Wood | Production Manager |
| Milt Rice | Special Effects |
| Don Stott | Gaffer |
| Billy Wilder | Director |
| Alice Monte | Hairstylist |
| Hal W. Polaire | Assistant Director |
| David Salven | Assistant Director |
| Del Harris | Sound Effects Editor |
| Robert Martin | Boom Operator |
| William Schurr | Camera Operator |
| Sid Sidney | Music Editor |
| John Williams | Orchestrator |
| Joe Palma | Stand In |
| Doane Harrison | Associate Producer |
| May Wale Brown | Script Supervisor |
| Tom Plews | Property Master |
| I. A. L. Diamond | Associate Producer |
| Fred Lau | Sound Designer |
| Gordon Sawyer | Sound Designer |
| Forrest T. Butler | Costume Designer |
| Miriam Nelson | Choreographer |
| Billy Wilder | Screenplay |
| I. A. L. Diamond | Screenplay |
| Alexandre Trauner | Production Design |
