Bon Iver ( BONE ee-VAIR) is an American indie folk band founded in 2006 by singer-songwriter Justin Vernon. Vernon had originally formed Bon Iver as a solo project, but it eventually became a band consisting of Vernon (vocals, guitar), Sean Carey (drums, keyboards, vocals), Michael Lewis (vocals, baritone guitar, guitar, violin, saxophone), Matthew McCaughan (drums, bass, vocals), Andrew Fitzpatrick (guitar, keyboards, vocals), and Jenn Wasner (guitar, keyboards, vocals)

Vernon released Bon Iver's debut album, For Emma, Forever Ago, independently in July 2007. The majority of the album was recorded while Vernon spent three months isolated in a cabin in western Wisconsin. In 2012, the band won the Grammy Award for Best Alternative Music Album for their eponymous album Bon Iver. They released their third album 22, A Million to critical acclaim in 2016. Their latest album, I, I, was released in 2019. The album was nominated at the 2020 Grammy Awards for Album of the Year.

The name "Bon Iver" derives from the French phrase bon hiver (pronounced [bɔn‿ivɛʁ]; 'good winter'), taken from a greeting on 1990s TV series Northern Exposure.