• Once In A Lifetime, a 1982 novel by Danielle Steel.
• "Once in a Lifetime", a 1930 comedy by George S. Kaufman and Moss Hart.

film

• Once in a Lifetime (documentary), a 2006 documentary about the New York Cosmos soccer team.
• "Once in a Lifetime" (Eureka episode), an episode of the television series Eureka.

music

• "Once in a Lifetime" (Eurovision song), a song that represented Estonia in Eurovision 2000
• "Once in a Lifetime" (Gregorian song), a song from Sadisfaction, later covered by Sarah Brightman on her Dive album.
• "Once in a Lifetime" (Keith Urban song), a song from Love, Pain & the whole crazy thing
• "Once in a Lifetime" (Talking Heads song), a song from Remain in Light
• Once in a Lifetime (box set), a box set by Talking Heads