| Most recent season or competition: 2024 NBL1 season | |
 | |
| Sport | Basketball |
|---|---|
| Founded | 2019 |
| First season | 2019 |
| General Manager | Dean Anglin |
| No. of teams | 20 (South Conference) 12 (North Conference) 10 (Central Conference) 14 (West Conference) 16 (East Conference) |
| Country | Australia |
| Continent | FIBA Oceania (Oceania) |
| Most recent champion(s) | M: Knox Raiders (2nd title) W: Waverley Falcons (1st title) |
| Most titles | M: Knox Raiders (2 titles) W: Multiple (1 title) |
| Sponsor(s) | Mitsubishi |
| Level on pyramid | 2 |
| Related competitions | NBL |
| Official website | NBL1.com.au |
The NBL1 is a semi-professional basketball league in Australia run by the National Basketball League (NBL). The league consists of five conference: NBL1 South, NBL1 North, NBL1 Central, NBL1 West and NBL1 East, with each consisting of both men's and women's competitions. Each conference is run by their respective state governing body, with the league including 72 clubs from across every state and territory.
The NBL1 in 2019 was a single league and consisted of one conference. That conference would go on to become the South Conference in 2020 after the inclusion of the former Queensland Basketball League (QBL) and South Australian Premier League saw them become the new North and Central conferences. The league grew to four conferences in 2021 with the inclusion of the former WA State Basketball League (SBL) and then five conferences in 2022 with the inclusion of the former NSW Waratah League.