"If You Leave Me Now" is a song by the American rock group Chicago, from their album Chicago X. It was written and sung by bass player Peter Cetera and released as a single on July 30, 1976. It is also the title of a Chicago compilation album released by Columbia Records (Columbia 38590) in 1983.
The single topped the Billboard Hot 100 on October 23, 1976, and stayed there for two weeks, making it the first number one hit for the group. It hit the number one on the Easy Listening charts[6] and was also Chicago's biggest hit internationally, topping the charts in other countries such as the UK, Australia, Ireland, Canada, and Netherlands. In the UK, it maintained the number one position for three weeks.[7] It was one of five "non-disco" songs to make it to number one in the US in a nine-month period of 1976.[8] According to writer Zachary Houle of PopMatters, "The song was so pervasive on radio upon its release that, reportedly, those tuning in in New York could hear the song playing on four different stations, each with varying formats, simultaneously."[9]
In 2010 Chicago teamed with the American Cancer Society and offered the opportunity to bid on the chance to sing their hit, "If You Leave Me Now" with them on stage live at their concerts, with proceeds going to the American Cancer Society to fight breast cancer.[17] The fund raising effort has continued in succeeding years.[18][19][20]