"Love the One You're With" is a song by folk rocker Stephen Stills. It was released as the lead single from his debut self-titled studio album in November 1970. The song, inspired by a remark Stills heard from musician Billy Preston, became his biggest hit single, peaking at No. 14 on the Billboard Hot 100 in early 1971.David Crosby and Graham Nash, Stills' fellow members of Crosby, Stills & Nash, provide background vocals on the song. The song was also covered by a number of artists, including The Isley Brothers, Bucks Fizz, and Luther Vandross.

Stills wrote the song after being inspired by the tag line — "If you can't be with the one you love, love the one you're with" which was a frequent remark by musician Billy Preston. Stills asked him for permission to use the line in a song and Preston agreed immediately.

A live version by Crosby, Stills, Nash and Young appears on their album 4 Way Street. A solo version by Stills appears on the Crosby, Stills and Nash CD Demos.

Several acts have since covered the song. The most notable cover came in 1971 from The Isley Brothers, whose unique gospel-driven cover of the song sent it to the charts again reaching number three R&B and number eighteen pop, giving the group their fifth US top 40 pop single.

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