
| Name | Show | Role Size | Age | Gender | Voice |
| Alcindoro | La bohème | supporting | 25 - 40 | male | bass |
| Alcolom | Chu Chin Chow | lead | 30 - 50 | female | |
| Alderman | New Girl in Town | N/A | - | male | |
| Alderman Joseph Helliwell | When We Are Married | lead | 50 - 59 | male | spoken |
| Aldolpho | The Drowsy Chaperone | supporting | 25 - 40 | male | |
| Aldonza (Dulcina) | Man of La Mancha | lead | 35 - 55 | female | soprano |
| Alec | Pipe Dream | cameo | - | male | |
| Alec | Anne & Gilbert | cameo | 15 - 20 | male | |
| Alec Harvey | Brief Encounter/Still Life | lead | 30 - 45 | male | spoken |
| Alec Hurley | Sing a Rude Song | N/A | - | male | |
| Aleksandr Serebryakov | Uncle Vanya | supporting | 50 - 60 | male | spoken |
| Aleksei Ivanovich Zharkov | The Captain's Daughter | cameo | 22 - 32 | male | tenor |
| Alençon | Henry VI, part 1 | supporting | 30 - 50 | male | spoken |
| Alessandro | Il re pastore (The Shepherd King) | lead | 35 - 50 | male | tenor |
| Alex | Merrily We Roll Along | cameo | 30 - 40 | male | |
| Alex | Wish You Were Here | cameo | 21 - 32 | male | |
| Alex | Lost in the Stars | supporting | 6 - 12 | male | soprano |
| Alex | Halcyon Days | lead | 20 - 30 | male | spoken |
| Alex Barton | DuBarry Was a Lady | supporting | 25 - 40 | male | |
| Alex Dillingham | Aspects of Love | lead | 17 - 34 | male | tenor |