Born in New York City on April 4, 1906. Bea grew up in San Francisco where she attended the St. Rose Academy High School. Following graduation, Bea attended the Reginald Travis School of Acting, also in San Francisco.
Young Bea made her professional debut at the age of 12 doing voice work in radio. She was discovered by the manager of KGO radio while performing in a children's production of The Beggar's Opera, who hired her as a singer.
She had a prolific career, working in such radio stalwarts as Fibber McGee and Molly, The Great Gildersleeve, The Adventures of Ozzie and Harriet, My Favorite Husband with Lucille Ball, and The Jack Benny Show. She provided the voice for literally hundreds of different characters.
Bea made the move to TV from radio in 1950, portraying Blanche Morton on The George Burns and Gracie Allen Show, a role she held for 8 years. Her work on this program caused her to pass up an offer by Lucille Ball and Desi Arnaz to portray neighbor Ethel Mertz on their new TV show I Love Lucy in 1951.
Bea Benaderet continued her voice characterization work, giving voice to many Warner Brothers cartoon characters. She was the original voice of Betty Rubble on the popular Flintstones cartoon series which began in 1960. She worked alongside of legendary voice man Mel Blanc, providing the female voices that Blanc couldn't do.
When Paul Henning was casting his The Beverly Hillbillies TV show in 1962, he considered Bea for the part of Granny Clampett. Henning instead chose Irene Ryan for the role, using Bea as Cousin Pearl Bodine instead. Later Henning returned to Benaderet, tapping her for the role of Kate Bradley on Petticoat Junction. She was with the series from its inception in 1963 until her death in 1968.
Her first marriage was in 1938 to actor Jim Bannon, a union which produced two children, Jack and Maggie. Jack grew up and followed his parents into acting. The couple were divorced in 1950. Bea remarried in 1957 to Eugene 'Gene' Twombley, a marriage which endured until her death.
Bea Benaderet died of lung cancer on October 13, 1968. Her husband Gene Twombley died just four days later of a heart attack. She is interred at Pierce Brothers Valhalla Memorial Park in North Hollywood, Los Angeles County, California.