Eva Cassidy was the third of four children born to Hugh and Barbara Cassidy. From an early age, she displayed artistic and musical talent. When she was nine years old, her father taught her to play the guitar, and she began to play and sing at family gatherings.
While a student at Bowie High School, she sang with a local band called Stonehenge, and received considerable praise.
At the age of eighteen, Cassidy began her professional career, singing and playing guitar in a Washington, D.C., area band, called Easy Street. This band performed in a variety of styles, at weddings, corporate parties, and pubs.
During the summer of 1983, Cassidy sang and played guitar, six days per week, at Wild World, in Maryland. Her brother Dan was also a member of this working band.
Throughout the 1980s, Cassidy worked with a number of other bands, including the soul and Motown-oriented band The Honeybees, and the techno-pop band Characters Without Names, later called Method Actor.
During this period, Cassidy also worked as a propagator at a plant nursery and as a furniture painter in Annapolis, Maryland. In 1986, she met (bassist and recording engineer) Chris Biondo, who encouraged her and helped her find work as a backup singer for various acts. In 1990, Biondo and Cassidy hired the so-called Eva Cassidy Band, composed of Chris Biondo, Lenny Williams, Keith Grimes and Raice McLeod, and she began to perform frequently in the Washington area.