"SOS" is a song by Barbadian singer Rihanna from her second studio album, A Girl like Me (2006). It was released on February 13, 2006, through Def Jam Recordings as the lead single from the album.
"SOS" was written by J. R. Rotem and E. Kidd Bogart with credit also assigned to Ed Cobb since the song is built around a sample of Soft Cell's 1981 recording of "Tainted Love", a song written by Cobb in 1965. Production of the dance and dance-pop song was handled by Rotem. Critical reception of "SOS" was generally positive, with the majority of music critics praising the inclusion of the "Tainted Love" sample. Some critics compared "SOS" to Rihanna's debut single, "Pon de Replay".
"SOS" became a commercial success. In the United States, it topped the Billboard Hot 100 chart for three consecutive weeks, becoming Rihanna's first number one single on the chart. "SOS" peaked at number one on the US Hot Dance Club Songs chart and Mainstream Top 40 chart. "SOS" was certified triple platinum by the Recording Industry Association of America (RIAA) for sales and streams of 3,000,000 units. The song was also successful in Europe as well as Australia, where it spent eight consecutive weeks at number one.
Three music videos were shot for "SOS"; aside from the official music video, directed by Chris Applebaum, promotional campaign videos were shot for lingerie brand Agent Provocateur and Nike. "SOS" was performed live at the 2006 MTV EMA awards in Copenhagen, Denmark.
"SOS" was included on the set list of the Good Girl Gone Bad Tour (2007–09) and the Last Girl on Earth (2010–11), which saw Rihanna perform a rock-tinged version of the song.