
| Name | Show | Role Size | Age | Gender | Voice |
| Adele Rice | A Man of No Importance | supporting | 17 - 25 | female | soprano |
| Adelia | Adelia | lead | 15 - 25 | female | soprano |
| Adelina | Gianni di Calais | N/A | - | female | soprano |
| Adelina | Song of Norway | N/A | - | female | |
| Adi | Milk and Honey | supporting | 20 - 32 | male | |
| Adina | L'elisir d'amore (The Elixir of Love) | lead | 18 - 28 | female | soprano |
| Admeto (Admetus) | Alceste (Italian version) | lead | 35 - 45 | male | tenor |
| Admetus | Alcestis | lead | 30 - 40 | male | spoken |
| Admiral Boom | Mary Poppins | N/A | - | male | |
| Admiral Peary | Ragtime | cameo | 35 - 65 | male | baritone |
| Admiral Potties | Ankles Aweigh | N/A | - | male | |
| Admiral von Shreiber | Sound of Music | cameo | 40 - 60 | male | |
| Ado Annie Carnes | Oklahoma | supporting | 18 - 25 | female | soprano |
| Adolar, Count of Nevers | Euryanthe | lead | 30 - 40 | male | tenor |
| Adolescent Elizabeth | Frankenstein | cameo | 15 - 20 | female | spoken |
| Adolescent Girl | Seal Skin | lead | 12 - 22 | female | spoken |
| Adolescent Henry | Frankenstein | cameo | 15 - 20 | male | spoken |
| Adolescent Victor | Frankenstein | cameo | 15 - 20 | male | spoken |
| Adolfo Pirelli | Sweeney Todd | supporting | 30 - 50 | male | tenor |
| Adolph Marx (Harpo) | Minnie's Boys | N/A | - | male |