Louis William Tomlinson (; born Louis Troy Austin; 24 December 1991) is an English singer and songwriter. He rose to fame as a member of the boy band One Direction. Tomlinson began his career appearing in television dramas before he auditioned on the British music competition series The X Factor in 2010. After being eliminated as a solo performer, he was placed into a group with four other contestants, forming One Direction. One Direction went on to become one of the best-selling boy bands of all time.

Following the group's hiatus in 2016, Tomlinson released "Just Hold On" as a debut solo single in December 2016. It peaked at number two on the UK Singles Chart and was certified platinum in the UK. In 2017, Tomlinson released "Back to You" with American singer Bebe Rexha (which was certified platinum in the USA and the UK) and "Miss You". In the same year, he appeared on Debrett's 2017 list of the most influential people in the UK.In 2018, Tomlinson appeared on the fifteenth series of The X Factor as a judge and a mentor of the "Boys" category. When his mentee Dalton Harris won the competition, Tomlinson became the first former contestant of the show to become the winning mentor. The following year, Tomlinson released the singles "Two of Us", "Kill My Mind", "We Made It", "Don't Let It Break Your Heart" and "Walls". His debut solo album, Walls, was released in January 2020.