Eonycteris major roosts in limestone caves throughout its range and has been recorded from sea level to ca 1,300 m near Borneo Highlands in Sarawak (Lim 1965, Mohd-Azlan et al. 2006). It is thought to be a canopy species as is infrequently encountered in bat surveys conducted in the forest understory. The species occurs across a range of forested habitats, from mixed lowland dipterocarp forest (e.g., near Loagan Bunut National Park) to lower montane forest near Borneo Highlands (Mohd-Azlan et al. 2006, Jayaraj et al. 2011).

The species has been captured in an orchard within Sungai Dewata (Pounsin et al. 2016) and has been collected in banana mixed garden habitats close to caves (A. Suyanto pers. comm.). While the species has been historically captured in heavily modified agricultural landscapes (e.g., rice fields and rubber plantations at Kampung Pangkalan Kuap South of Kuching, Lim 1965), more recent research has only documented it at the interface between forests and oil palm plantations (Mohd-Azlan et al. 2019) or in forests adjacent to oil palm plantations near Lambir Hills National Park (LHNP), Sarawak, Malaysia (Fukuda et al. 2009). It has also been documented (three individuals) in regenerated montane forests (1,000 m) at Mount Penrisen, Padawan (Jayaraj et al. 2011). Notably, 16 individuals (five male, 11 female) were captured at Kolej Universiti Sains Malaysia which was built on recovered mangrove land (Fadhullah and Ho 2013). Conversely, only three (3) individuals were confirmed at the Crocker Range Biosphere Reserve, one in the biosphere’s buffer and two in extralimital agricultural landscapes (Yoh et al. 2020). Additional research on the species habitat associations, especially with primary forests across an elevational gradient is warranted.

Eonycteris major is endemic to Borneo and has been documented in Brunei, Indonesia, and Malayasia. Previous records of the species from Mentawai Islands have been excluded from this assessment as it is thought to be a large example of spelaea (Corbet and Hill 1992); Helgen (pers. comm.) suggests it may represent an undescribed subspecies.

There are no species-specific conservation initiatives in place for E. major. Conservation of known cave roosts is warranted as is protection of primary forests, especially near known roosts. This species receives Protection status in Sarawak under the Sarawak Wildlife Protection Ordinance 1998, but is not considered as a species of conservation importance in Sabah. It has been documented in at least one biosphere reserve (Crocker Range Biosphere Reserve; Yoh et al. 2020). Additional research is needed on the species population status and trends, distribution, habitat and ecology, and threats.