Born in New Orleans, Rayner went to Milan in 1924 for vocal studies, which led to his debut in 1927, in Rome, as Rodolfo in La bohème. He was often heard at the Opéra-Comique and the Berlin Staatsoper.
On May 23, 1936, the tenor made his Metropolitan Opera debut, as Don José in Carmen, opposite Bruna Castagna. He appeared with that company through 1938, in Aïda (with Elisabeth Rethberg), Cavalleria rusticana (with Rosa Ponselle), Carmen again (opposite Ponselle), Les contes d'Hoffmann (conducted by Maurice Abravanel and directed by Herbert Graf), Manon (with Bidu Sayão in her Met debut, later with Grace Moore), Faust, and Pagliacci (opposite Robert Weede in his Met debut).
Rayner died at the age of eighty-six, in East Patchogue.
- Sydney Rayner in an excerpt from Manon (audio only, 1937). 
- Metropolitan Opera (Performance archives on the MetOpera Database). Rayner, Sydney (Tenor).
- The New York Times (September 15, 1981). "Sydney Rayner, 86; Tenor at Met Opera in the 30s, is Dead". (subscription required)