(in order of appearance)
| Apollo: | the god of light, music, and prophecy, who is indebted to Admetus for his hospitality |
| Death: | the god of death, jealous of his privileges |
| Chorus of Thessalians: | men and women of the town of Pherae, where the play takes place |
| Selena: | a servant of the household |
| Admetus: | king of Pherae, famous for his hospitality |
| Alcestis: | his devoted wife |
| Children: | the two unnamed children of Admetus and Alcestis |
| Heracles: | the great hero and strongman, famous for his appetites |
| Pheres: | the aged father of Admetus |
| Aoide: | another servant of the household |