Saccolaimus flaviventris forages across a wide variety of habitats, including eucalypt forests, woodlands and open habitats. It can be relatively abundant in some tall forests of northern Australia, likely ranging several tens of kilometres each night (K.N. Armstrong unpublished data), and its use of large trees in riparian areas probably help it to expand its range into woodlands with relatively low tree height. It roosts in tree hollows, usually singly but sometimes in groups of up to 10, though breeding colonies may exceed 1oo individuals. It may make migratory movements in the south-eastern portion of its range during autumn, although most records from south-eastern Australia are of exhausted individuals found in exposed situations, which might indicate they are vagrants blown off-course. Seasonal movements might also occur in the mid-coastal Western Australian range (N. McKenzie pers. comm).

It is present in many protected areas throughout Australia. Targeted surveys in Papua New Guinea are needed to more clearly define extent of occurrence and habitat association. Further ecological research is needed to investigate its status in the southern parts of its range as well as its basic ecology and roosting habits.