She appeared on Broadway and on television. From 1967 to 1969, she co-starred in the NBC sitcom, The Mothers-in-Law, with Eve Arden. She also appeared as a regular on The Doris Day Show from 1970-1972.
Ballard established herself as a musical comedienne in the 1940s, joining the Spike Jones touring revue of entertainers. Capable of playing broad physical comedy as well as stand-up dialogue routines, she became a familiar face in television and stage productions. In 1957, she and Alice Ghostley played the two ugly stepsisters in the live telecast of Rodgers & Hammerstein's Cinderella, starring Julie Andrews in the title role. She made appearances on the American television game showMatch Game, and in 1976 was a guest star on The Muppet Show.
On Broadway, she has starred as Helen in The Golden Apple, where she introduced the song "Lazy Afternoon". She also portrayed Rosalie in Carnival (with Jerry Orbach), and Ruth in Joseph Papp's production of The Pirates of Penzance. She closed out-of-town in Marc Blitzstein's Reuben, Reuben and played Hattie Walker in the Paper Mill Playhouse's 1998 revival of Stephen Sondheim's Follies. She also appeared as Molly Goldberg in an unsuccessful musical adaptation of the popular radio serial. In 2005, she appeared in a road-company production of Nunsense, which was written by Dan Goggin. She recently completed her autobiography, How I Lost 10 Pounds in 53 Years.
A breast cancer survivor, she has never married.