Single Ladies (Put a Ring on It) is a song from Beyoncé's third studio album, I AM... SASHA FIERCE. Columbia Records released Single Ladies as a single on October 13, 2008 as a Double A-side alongside, If I Were a Boy, showcasing the contrast between Beyoncé and her aggressive onstage alter ego, Sasha Fierce. It explores men's unwillingness to propose or commit. In the song, the female protagonist is in a club to celebrate her single status. Single Ladies won three Grammy Awards in 2010, including Song of the Year, among other accolades. Several news media sources named it as one of the best songs of 2008, while some considered it one of the best songs of the decade. It topped the US Billboard Hot 100 chart for four non-consecutive weeks and has been certified quadruple-platinum by the Recording Industry Association of America (RIAA). The song charted among the top ten within the singles category in several other countries. Globally, it was 2009's seventh best-selling digital single with 6.1 million copies sold thus becoming one of the best-selling singles of all time.

A black-and-white music video accompanied the single's release. It won several awards, including the Video of the Year at the 2009 MTV Video Music Awards. Beyoncé has performed Single Ladies on television and during her concert tours. The song and particularly its music video have been widely parodied and imitated. Several notable artists have performed cover versions. Media usage has included placement in popular television shows.

Community content is available under CC-BY-SA unless otherwise noted.