In 1954, Richardson moved with her family to Toronto.
Richardson was a member of 1960s Toronto-based girl group The Tiaras along with Brenda Russell. She is of African-American descent, and was born near Pittsburgh.
The musical Big Mama! The Willie Mae Thornton Story was conceived of and written by Audrei-Kairen Kotaska for Richardson, who starred in the production first in 1999 and then again in 2012.
Richardson is a three-time nominee for the Academy of Canadian Cinema and Television Gemini Award, and won the Gemini Award for Best Performance by an Actress in a Leading Role in a Dramatic Program or Mini-Series for The Gospel According to the Blues. In 2003 she was nominated for the NAACP Image Award for Best Actress in a Television Movie for Sins of the Father. Richardson is also a noted stage performer, winning a Dora Award in 2004 for the musical Cookin' at the Cookery. Other high-profile projects include Milk and Honey, More Tales of the City, Further Tales of the City, and 3 Men and a Baby.
In 2017, Richardson won Martin Luther King Jr. Achievement Award for their theater and music achievements.