"SOS" (working title; "Turn Me On") was written by Benny Andersson, Björn Ulvaeus and Stig Anderson and was recorded at Glen Studio in Långängen, Sweden on 22–23 August 1974.

[3] "SOS" was among the first of three songs recorded for the group's 1975 album, ABBA and the opening track of their classic Greatest Hits LP released at the end of the same year.

[3] During the band's first visit to the United States, ABBA performed "SOS" on the long-running television programs American Bandstand and Saturday Night Live on 15 November 1975.

[20] "SOS" has been recorded and performed in concert by several prominent artists, including John Frusciante, Peter Cetera, Chris deBurgh, Cher, Portishead, Fozzy, and Canadian rock group Headstones.

English synth-pop duo Erasure covered "SOS" and three other ABBA songs on their 1992 Abba-esque EP, reaching number one in the UK singles chart.

[23] American singer-songwriter and former Czars frontman John Grant has called "SOS" "one of the greatest pieces of music ever made", adding that Agnetha Fältskog's "perfect" lyrical interpretation and emotional delivery is "a beautiful thing".

[7] British conductor and producer Charles Hazlewood called the song's "supersonic" transition from an acoustic D-minor key to an electric rock motif "absolutely genius".

[7] Sex Pistols bassist Glen Matlock has claimed to have been inspired to write the main riff of "Pretty Vacant" after hearing "SOS" on a jukebox.

[27] ABBA performed "SOS" on episode five of the inaugural season of the long-running comedy-variety show Saturday Night Live (SNL) on 15 November 1975.

[73] Writing for Rolling Stone, Brittany Spanos felt that "working with producer Mark Taylor who helped seal Cher’s legacy with the game-changing "Believe" in the late Nineties, she finds subtle changes that update ABBA classics without totally stripping them of the catchiness that made those songs beloved hits well beyond their heyday.

(A Man After Midnight)," "SOS" and "Mamma Mia" are given just enough of a knob turn that they're transformed from upbeat FM radio pop into club bangers, pulsating with every beat.

The video features Rumer Willis, singer Betty Who, Transparent star Trace Lysette, comedian Sabrina Jalees, Elena of Avalor voice actor Aimee Carrero and Crazy Ex-Girlfriend cast member Vella Lovell.

Roytel Montero said that "in a studied homage to the original ABBA classic from 1975, [the] interpretation of the video renders it a poignant call to female solidarity".