The most successful team in S.League history is the Singapore Armed Forces Football Club (SAFFC), which has won the title seven times (1997, 1998, 2000, 2002, 2006, 2007 and 2008), and also finished runners-up four times (1996, 1999, 2001 and 2005).
To help promote the development of top young players in Singapore, a team known as the Young Lions was introduced to the S.League in 2003, made-up largely of the members of the Singapore national under-23 team.
Seven non-Singaporean teams have been involved in the S.League:
* Albirex Niigata FC (Singapore) (a satellite team of Albirex Niigata, a top-level professional club in Japan's J. League),
* Dalian Shide Siwu FC (a satellite team of Dalian Haichang, a top-level professional club in China's Super League),
* DPMM FC (a team from Brunei, playing home games in Brunei, formally of Malaysian football league),
* Sinchi FC (a team made up of players from China),
* Sporting Afrique FC (made up of players of African origin),
* Liaoning Guangyuan FC (a satellite team of Liaoning FC, a top-level professional club in China's Super League), and
* Super Reds FC (made up of players from South Korea).
The S.League also operates a Reserve cum Youth Tournament known as the Prime League.