Hall and her twin sister, Andrea Hall, were born in Milwaukee, Wisconsin and raised in Lake Worth, Florida. At age 12, Hall was elected Junior Orange Bowl Queen. She is a graduate of Lake Worth High School, Class of 1965.

Along with her sister, Andrea, Hall appeared in press materials for the 1952 Hudson Twin-H-Power engine.

In the 1970s, she appeared as the superheroine Electra Woman in "ElectraWoman and DynaGirl", a Sid and Marty Krofft children's show.

Hall appeared on a number of shows, including Emergency! (as Nurse Sally Lewis), and The Young and the Restless (as Barbara Anderson), before joining Days of our Lives in 1976 as Dr. Marlena Evans.

In 1986, Hall began playing Jesse Witherspoon on the family drama, Our House, which ran for two seasons. Hall exited Days of our Lives in 1987 when it became too difficult to co-ordinate her prime time and daytime schedules.

Hall continued to make guest appearances on a variety of prime time shows until 1991, when she made a dramatic return to Days of our Lives. Hall has remained on the show since then, and has been involved in some of the most controversial storylines of the show's history.

In 1995, Hall produced and starred in Never Say Never: The Deidre Hall Story, a made for TV movie about her personal struggles to become a mother.

According to Soap Opera Digest, as of November 17th, 2008, she, along with Drake Hogestyn (her on-screen husband), have been dismissed from the show. NBC renewed the show for a few more seasons but significantly dropped the amount of money they would pay for the show. Both Hall and Hogestyn were dropped as a result of the large budget cut by NBC.

Since at least early 2009, Hall has occasionally guest-hosted Clout, a talk radio program syndicated through Air America Media.

Hall has donated $1,000 to the campaign of Representative Dennis Kucinich for President.