The collared mongoose is found on the islands of Borneo (Malaysia: states of Sarawak and Sabah [Wells et al. 2005; Wong Siew Te pers. comm., J. Hon, pers. obs.]), Indonesia [van Strien 2001] and presumably Brunei, although no records have been traced) and on Sumatra (Indonesia Robinson and Kloss, 1919). The range on Borneo is much more extensive than depicted in Corbet and Hill (1992), with records from the Balikpapan area, Gunung Palung, and Kutai and museum records from Balikpapan, Kendawangan, Pontianak, and Sanggau (see van Strien 2001). In Sumatra, there are only two confirmed historical locality records; two individuals (including the holotype of H. s. uniformis) from Ayer Taman in Ophir District in W. Sumatra (300 m) adjacent to Gunung Paseman (Robinson and Kloss, 1919). The southern record from Jentink (1894) mentions one specimen from Soekadana, South Sumatra. No recent records have been traced from Sumatra.