South Australian National Football League

The South Australian National Football League, or SANFL (/ˈsænfəl/ or S-A-N-F-L), is an Australian rules football league based in the Australian state of South Australia. It is also the state's governing body for the sport.

Originally formed as the South Australian Football Association on 30 April 1877, the SANFL is the oldest surviving football league of any code in Australia and is the 7th-oldest club football league in the world. For most of its existence, the league was considered one of the traditional "big three" Australian rules football leagues, along with the Victorian Football League and West Australian Football League. Since the introduction of two South Australia-based clubs into the Australian Football League – the Adelaide Crows in 1991 and the Port Adelaide Power in 1997 – the popularity and standard of the league has decreased to the point where it is considered a feeder competition to the Australian Football League.

Consisting of a single-division competition since the admission of the Adelaide Crows reserves in 2014, the season has since been a 10-team, 18-round home-and-away (regular) season from April to September. The top five teams play off in a final series culminating in the grand final for the Thomas Seymour Hill Premiership Trophy. The grand final had traditionally been held at Football Park in October, generally the week after the AFL Grand Final, though this was altered ahead of the 2014 season, resulting in Adelaide Oval hosting the grand final in the penultimate weekend of September.

The semi-professional league is considered the strongest competition after the fully professional Australian Football League (AFL) . The league owned the sub-licences for South Australia's two AFL clubs—Adelaide Football Club and Port Adelaide Football Club—until March 2014, when South Australian Football Commission reached an agreement with the Adelaide and Port Adelaide clubs—endorsed by the AFL—which will see the two AFL licences transferred to the clubs in return for payments totalling more than $18 million.

The league is also responsible for the management of all levels of football in the state. This includes junior football, country football, amateur football and specific programs rolled out across schools, indigenous communities (including the APY Lands in the state's north) and newly arrived migrant communities.

The SANFL owned Football Park, formerly the largest stadium in South Australia. The stadium, which opened in 1974, was primarily used for Australian Football League matches up until 2013 and had a capacity of over 51,000 prior to being demolished. The stadium was the headquarters for the league from 1974 to 2013. The SANFL competition is the second highest attended Australian rules football league behind the AFL.