The S. G. Ball Cup is a junior rugby league football competition played predominantly in New South Wales, between teams made up of male players aged under 19.

Teams from Canberra and Melbourne, and Auckland (New Zealand Warriors) also participate.

Prior to the COVID-19 pandemic in New South Wales a team from Perth (West Coast Pirates) also participated.

After the sixth round on March 14 & 15, the 2020 competition was suspended and subsequently cancelled due to the COVID-19 pandemic in Australia.

[1] Three teams from 2020 that did not return in 2021 were: Previous teams that participated in the SG Ball Cup include: Gold Coast Titans (2008–09), Newtown Jets (1970s, early 1980s & 2009), Western Sydney Academy of Sport (2007–17).