SOS (ABBA song)

"SOS" is a song by the Swedish pop group ABBA, recorded for their eponymous third album ABBA (1975). The track features Agnetha Fältskog on lead vocals, and was written by Björn Ulvaeus, Benny Andersson, and Stig Anderson, and produced by Ulvaeus and Andersson. It was released on 3 June 1975 as the fifth single from the album via Polar Music. No singular B-side was issued, although "Man in the Middle" was used in most releases. Fältskog later recorded the song in Swedish for her 1975 solo album Elva kvinnor i ett hus.

A turning point for the group, "SOS" became the group's first major worldwide hit since "Waterloo". Notably, it brought the group back into the top ten in the United Kingdom, a market where they had struggled to thrive in following "Waterloo"; it peaked at number six on the UK singles chart. "SOS" reached the top spot in Australia, Belgium, New Zealand, South Africa, and West Germany, and reached the top ten in most countries. The song also became the group's second overall top ten hit in the United States, peaking at number ten on the Record World Singles chart.

"SOS" has been recognized as one of the group's greatest records, with many artists praising its composition and using it as inspiration for their own records.