| Lewton, Randall (2) | Liberatore, William (1) | Lichte, Erick (1) |
| Lichtenstein, Jonathan (2) | Lieberman, Susan (1) | Lim, Emily (1) |
| Limber, Chris (1) | Lindberg, Trish (1) | Lindblad, Sharon (1) |
| Linden, Sonja (2) | Linder, Evan (1) | Linderman, Ed (1) |
| Lindle, Darian (1) | Lindsay, Joan (2) | Lindsay, Howard (6) |
| Lindsay-Abaire, David (2) | Lindsey-Nassif, Robert (0) | Linehan, Graham (1) |
| Liner, Elaine (2) | Link, William (4) | Linney, Romulus (1) |
| Lion, Margaret (0) | Lipez, Erica (1) | Lippa, Louis (2) |
| Lippa, Andrew (9) | Lippman, Anna (0) | Lipton, Ethan (1) |
| Liptrot, Amy (1) | List, Bo (1) | Lithwick, Dahlia (1) |
| Little, Larry (3) | Little, Mindy Manley (1) | Littlewood, Joan (1) |
| Lizzimore, Clare (1) | Llosa, Mario Vargas (1) | Lloyd, Jeremy (3) |
| Lloyd, Richard (1) | Lloyd Malcolm, Morgan (4) | Lloyd Webber, Andrew (19) |
| Lochhead, Liz (14) | Lock, Kate (1) | Lockhart, Warren (2) |
| Lodato, Victor (1) | Loeb, Aaron (1) | Loewe, Frederick (3) |