Little Mix are an English girl group, formed on the British version of The X Factor, and the first group and only girl group to win the series. The line up consisted of Leigh-Anne Pinnock, Jade Thirlwall, Perrie Edwards, and originally Jesy Nelson, before her departure from the group in 2020. Regarded as the show's most successful winning act, their success led to a girl band renaissance in the UK. Little Mix's vocals and harmonies have garnered critical acclaim and the band are ranked amongst one of the best vocal girl groups. They were often dubbed by some media as the "biggest girl group in the world", before going on a hiatus in 2022, allowing its members to pursue solo projects.

A girl group is a music act featuring several female singers who generally harmonize together. The term "girl group" is also used in a narrower sense in the United States to denote the wave of American female pop music singing groups, many of whom were influenced by doo-wop and which flourished in the late 1950s and early 1960s between the decline of early rock and roll and start of the British Invasion. All-female bands, in which members also play instruments, are usually considered a separate phenomenon. These groups are sometimes called "girl bands" to differentiate, although this terminology is not universally followed.