NBL1 South is a semi-professional basketball league in Victoria and Tasmania, Australia, comprising both a men's and women's competition. In 2019, Basketball Victoria partnered with the National Basketball League (NBL) to create NBL1. NBL1 South was the lone conference in 2019, with North, Central, West and East joining over the proceeding three years. Due to the COVID-19 pandemic, the NBL1 South did not have a season in 2020 and only half a season in 2021.
The NBL1 in 2019 was a single league and consisted of one conference. After a successful first season, the NBL expanded the NBL1 in 2020 by introducing Basketball Victoria's inaugural 2019 league and teams as the new South Conference and partnering with Basketball Queensland and Basketball South Australia to make the Queensland Basketball League (QBL) and South Australian Premier League the new North and Central conferences.[4][5][6] However, due to the COVID-19 pandemic, the 2020 season was cancelled for all three conferences.[7]
On 1 September 2021, the 2021 NBL1 South season was cancelled due to the COVID-19 pandemic in Victoria. With a combined 154 men's and women's games that could not be completed, it was decided to abandon the season with no champions and no individual awards.[8]