The Singapore Football League (SFL) is an amateur football tournament for clubs that are affiliated to the Football Association of Singapore. It makes up the second and third tier of football in Singapore after the professional Singapore Premier League, which was established in 1996 and before the FAS Island Wide League. The teams are also eligible to compete in the Singapore FA Cup.
Although it is an amateur competition organized by the FAS, several former Singapore internationals and ex-S.League players have played in the league such as Jonathan Xu, Indra Sahdan Daud, Precious Emuejeraye and Ahmad Latiff (Eunos Crescent), Yazid Yasin (Gymkhana FC) and Zulkiffli Hassim (Yishun Sentek Mariners).
The history of the National Football League (NFL) can be traced back to the earliest 20th century during the British colonization of Singapore, whereby the Singapore Amateur Football Association (SAFA) was formed in year of 1892. SAFA was responsible for organising the top tier football leagues in Singapore with NFL as the top tier football league from early 20th century, until the formation of FAS Premier League in 1988. It was previously made up of Division 1, Division 2 and Division 3, with the bottom team of Division 3 being relegated to the FAS Island Wide League.
As of 2018, it makes up provisional tiers 2 and 3, behind the professional Singapore Premier League, with rules of promotion and relegation applied for teams in NFL Division One and NFL Division Two. Teams play two-round league home-away format. League features promotions and relegations for all the teams in both divisions, where the top two teams of a division will be promoted to the upper division, and the last two relegated to the lower division.
In 2020, the NFL was renamed as Singapore Football League (SFL). Due to the COVID-19 pandemic in Singapore, the first season of SFL started in 2022.