The English Football League One, often shortened to just League One, or sometimes Sky Bet League One for sponsorship reasons, is the second highest football division in England, and the third highest football league overall. The division was previously known for a long time as the Football League Third Division; however, after the invention of the Premier League in 1992, it was renamed Football League Second Division, later being renamed English Football League One, starting with the 2004 football season.
As of the 2018 – 2019 season, Walsall has held the longest tenure in League One, only having been moved out of the division for the 2006 to 2007 season, but managing to get promoted back into League One after then. Currently, seven teams are competing in League One which are former premiership teams: Barnsley, Blackpool, Bradford City, Charlton Athletic, Coventry City, Portsmouth, and Sunderland.
24 clubs compete in the league, with each club playing every other club twice during a season, once at home and once away. At the end of the season, the top two clubs are promoted up a division, and the bottom two clubs are demoted.