"Single Ladies (Put a Ring on It)" is a dance-pop and contemporary R&B song from American singer Beyonce's third studio album, I Am... Sasha Fierce (2008). Columbia Records released "Single Ladies" as a single on October 13, 2008 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.

Most music critics praised the song's smooth production and some noted its similarity to Beyonce's 2007 single "Get Me Bodied". "Single Ladies" won three Grammy Awards in 2010, 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.