The British star passed away on 23 November (10) in Santa Monica, California of natural causes, reports Variety.com.
Born in England, Howard studied at the Royal Academy of Dramatic Arts and starred in a number of London plays, including Romeo and Juliet at the Old Vic and A Streetcar Named Desire during World War II.
She then began working on films and starred with actor James Mason in thrillers including Terror House and They Met in the Dark.
Howard also carved out a career as an author, writing plays and two novels, and also as a Hollywood executive for Paramount TV.
She is survived by her three children, stepson Michael, a granddaughter and two great-grandchildren.