Born as Hannah Beatrice Kuper, Kay performed as "Honey Kuper" and "Honey Day" for part of her career in vaudeville, radio, motion pictures, sound recordings, night clubs, and television. Her career began at the age of six as "Little Lord Fauntleroy" in stock theater. She went on to becoming a headliner at Billy Rose's famed Diamond Horseshoe Nightclub in New York. She was on Mercury Theatre (directed by Orson Welles), and eventually hosted a radio show, The Beatrice Kay Show.
She appeared at top nightclubs including San Francisco's austere Fairmont Hotel Venetian Room, the Moulin Rouge in Paris, Hollywood's famed Ciro's in Los Angeles, and at the El Rancho Hotel in Las Vegas. She also recorded several phonograph albums, and appeared in a 1945 motion picture about the club where she had performed in her earlier years—Billy Rose's Diamond Horseshoe (the film starred Betty Grable and Dick Haymes).
She appeared with Cliff Robertson in 1961's Underworld U.S.A. and in 1969's A Time for Dying, with Victor Jory and Audie Murphy. In 1974, she had a bit part in the film Ginger in the Morning (which starred Susan Oliver, Sissy Spacek and Monte Markham).
Songs which she helped popularize include "A Bird in a Gilded Cage", "No! No! A Thousand Times No!!", "The Band Played On", "Mention My Name In Sheboygan", and "Ta-ra-ra Boom-de-ay".