Born in New York City, Margot Stevenson was the daughter of Reverend J. Ross Stevenson, who served as president of Princeton Theological Seminary, and Florence Day Stevenson. Her theatrical career began in the early 1930s.
Stevenson made her Broadway debut in 1932. Her most famous role came in 1941 when she was cast as Elaine Harper, the fiancée of Mortimer Brewster, in Joseph Kesselring's dark comedy Arsenic and Old Lace. The play was a critical and commercial success, running for 1,444 performances on Broadway. She also appeared in other Broadway productions throughout her career, including The Rugged Path and The Curious Savage.
Beyond the stage, Stevenson was a prolific performer during the Golden Age of Radio, lending her voice to various dramatic programs and series. While her primary focus was theater, she also made occasional appearances in film and television.
Margot Stevenson was married to actor Val Avery. She remained active in the theatrical community for much of her life and passed away in 2011 at the age of 99, leaving a legacy as a versatile and enduring figure in American acting.