This species is found in varied habitat types from primary and secondary forested regions, agricultural landscapes (including rubber plantations) to urban areas. It roosts in trees, crevices and cracks in walls and ceilings of houses, tiles of huts, old buildings, temples, under bark and in holes of large trees, signboards, tree hollows in small groups of few individuals. In Ho Chi Minh city colonies of several dozen individuals were reported in buildings (Kruskop 2013). This bat emerges early in the evening, before full darkness. Flight is moderately speed and maneuverable, sometimes fluttering (in cluttered places) as in most pipistrelles, in Ho Chi Minh bats were observed foraging in urban areas and city parks at about 6-15 m above ground or water (ibid.), however they were also observed much higher in the Red river valley. Javan pipistrelle probably forages on flies, winged ants and other small insects, though its ration was not described. There are three breeding seasons (though probably the same females may not reproduce in two consecutive seasons) and two young ones are born (Sanborn et al. 1952, Bates and Harrison 1997, Heaney et al. 1998, S. Bumrungsri pers. comm., P. Bates pers. comm., Bhargavi Srinivasulu pers. comm.). Echolocation are steep to shallow FM from ca. 75 to 45 kHz (Kruskop 2013).

This widespread species has been recorded from northern and central South Asia, southern China, and much of Southeast Asia. In South Asia this species is presently known from Bangladesh (Chittagong and Sylhet divisions,), India (Assam, Himachal Pradesh, Madhya Pradesh, Maharashtra, Manipur, Meghalaya, Nagaland, Nicobar Islands, Sikkim, Uttarakhand and West Bengal), Nepal (Central) and Pakistan (North West Frontier Province and Punjab) (Das 2003, Korad et al. 2007, Molur et al. 2002, Srinivasulu and Srinivasulu 2005). The records from Afghanistan erroneously attributed to this species have been identified as P. coromandra (Benda and Gaisler 2015). In South Asia, it has been recorded up to 2,380 m asl. In China, it has been recorded from Xizang and Yunnan (Smith and Xie 2008). In Southeast Asia, it ranges widely, from Myanmar in the west, through Thailand, Lao PDR, Viet Nam, Cambodia and Peninsular Malaysia to Singapore. With insular Southeast Asia, the species is distributed in Indonesia (Sumatra, Bangka, Java, Flores, Karakelang), the island of Timor (East Timor and Indonesia), on the island of Borneo (Brunei, Indonesia and Malaysia), Sulawesi, to the Philippines, where it has been recorded from the islands of Camiguin, Luzon (Benguet , Cagayan, Camarines Sur, Isabela, Laguna, Quezon, and Rizal provinces), Mindanao (Bukidnon, and Davao del Sur provinces), Mindoro, Negros, Palawan, Panay, Reinhard, and Sibuyan (Heaney et al., 1998). In the Philippines, it has been recorded from sea level to around 2,250 m asl (Mount Kitanglad).

This species occurs in a number of protected areas in Southeast Asia. In South Asia, although there are no direct conservation measures in place, the species has been recorded from several protected areas including Kanha National Park in Madhya Pradesh and Nagarjunasagar-Srisailam Tiger Reserve in Andhra Pradesh (C. Srinivasulu pers. comm. August 2018). In Vietnam this bat occurs in some protected areas, e.g. Vu Quang, Yok Don, Kon Chu Rang and Kon Ka Kinh (Kruskop 2013, 2017). Further studies are needed into the distribution, abundance, breeding biology and general ecology of this species, as well as taxonomy – to clarify taxonomic status of putative cryptic forms. Populations of this species should be monitored to record changes in abundance and distribution (Molur et al. 2002).