Summary Subtropical dry forests are among the largest and most threatened terrestrial biomes worldwide. In Argentina, the Native Forest Law (NFL) was passed in 2007 to regulate deforestation by mandating the provincial zonation of forested areas, while the erection of fences has been an increasingly common mechanism of private-land control reinforcement in the region; this is mainly fuelled by imminent land-use changes, recent land transactions or subsidies from the NFL. We explored the dynamics between the erection of fences and deforestation in the Northern Argentinian Dry Chaco (NADC) during the implementation of the NFL. We found that a third of land deforested during 2000–2017 had been previously fenced, with the highest percentage (44%) occurring during the sanction of the NFL (2007) and the completion of the forest-zonation maps (2011). Only 34% of deforestation within fenced areas occurred in zones where deforestation was legally permitted. In total, 327 386 ha of forests had been fenced within NADC by 2017, representing areas of potential access restriction for local people, who historically used forest resources for survival. Additionally, 57% of the fenced area occurred in zones where deforestation was restricted. A novel remote-sensing application can serve as an early-warning tool for deforestation.