First recorded by Keely Smith (1967).
Hit versions by Rosemary Clooney (MOR #28 1968), The 5th Dimension (US #2/MOR #1/R&B #4 1970).
From the wiki: “‘One Less Bell to Answer’ is a song written by Burt Bacharach and Hal David (“The Look of Love“, “I’ll Never Fall in Love Again“, “Alfie“), originally written for and recorded in 1967 by Keely Smith (‘I’m a Gigolo‘, with Louis Prima).
“The song was rediscovered in late 1969 by Bones Howe, the producer for the 5th Dimension, and the song was included on the group’s 1970 debut album for Bell Records, Portrait. Rosemary Clooney had, a year earlier, in 1968, first charted the song on the Billboard Easy Listening chart – one of her two last recordings before leaving show business.”
Rosemary Clooney, “One Less Bell to Answer” (1968):
(Video no longer available)
The 5th Dimension, “One Less Bell to Answer” (1969):