The veteran crooner sampled Cassidy's classic version of the Sting song Fields of Gold for a collaboration on his album Gems - The Duets Collection, which was released last year (11).
And in an appearance on talk show Loose Women on Monday, Bolton used a tape of Cassidy to 'duet' with her on the track, as poignant images of the late singer were shown on screen.
Presenter Carol Vorderman told viewers Bolton would be staging "a very special performance featuring vocals from the late, great Eva Cassidy - a woman made world famous by her version of this song".
Earlier in the show, Bolton told how he asked Cassidy's family for permission to use the recording of her voice on his album before laying down the track.
Cassidy died from skin cancer in 1996 at the age of 33.