Fire is a natural process in tropical savannas, but contemporary cycles of recurrent, extensive, severe fires threaten biodiversity and other values. In northern Australia, prescribed burning to reduce wildfire incidence is incentivised through a regulated emissions abatement program. However, only certain vegetation types are eligible; also, managers of small land parcels are disadvantaged by the program’s transaction costs and interannual variability in management outcomes. Both impediments apply to landholders of the Dampier Peninsula, north-west Australia. Nevertheless, Indigenous rangers, pastoralists and other stakeholders have collaborated for 5 years to manage fire across their small holdings (300–2060 km2). We used remote sensing imagery to examine the project’s performance against seven fire regime targets related to biodiversity, cultural and pastoral values. At the scale both of individual landholders and the entire Peninsula (18 500 km2), the project significantly reduced the extent of annual fire, high-severity fire, mid-late dry season fire, fire frequency and severe fire frequency. The project significantly increased the graininess of burnt and unburnt areas and the extent unburnt for 3+ years more than tripled. The project demonstrates that cross-tenure collaboration can overcome the challenges of managing fire on small land parcels. However, this project’s sustainability depends on securing ongoing funding.