In 1990, it was covered by Celine Dion for her album, Unison. It was released as the fourth single in Canada (March 1991) and the third in the United States (July 1991) and the rest of the world (September 1991). In the United Kingdom it was the second commercial single, because "(If There Was) Any Other Way" was issued as a promotional release only. The B-side included "Unison," which was released as a single in Canada and Japan only. The music video directed by Dominic Orlando was filmed in Hollywood, Los Angeles (1991). It became a part of the Unison home video. The song reached number 16 in Canada and number 7 on the Canadian Adult Contemporary Chart. "The Last to Know" had also a moderate success on the Hot Adult Contemporary Tracks chart in the United States, peaking at number 22.
Entertainment Weekly editor Jim Farber wrote: "Tracks like "If Love Is Out the Question" and "The Last to Know" are lush vehicles, filled with routine hooks that Dion's distinctive voice raises to a higher level."