A lifer is a person sentenced to life imprisonment; also a person who makes a career of one of the armed forces, or another profession; or a person who has made a lifelong commitment (as to a way of life).
Lifer or Lifers may also refer to:
Music Lifer (band), an American rock band "Lifer", a song by Down, from the album NOLA "Lifer", a 2016 song by Florida Georgia Line Lifer (album), a 2017 album by MercyMe Lifers, a 2018 album by Cody Jinks Lifers (album), a 2020 album by Local H
Film and television Lifer (2014 film), a 2014 short film by Ervin Chartrand
Other uses "Lifer" or "lifer bird", a bird species that has been seen for the first time, adding to a birdwatcher's life list