This speciesis distributed in Bolivia, Ecuador (east of the Andes), and Peru (to Cuzco Prov.).
This is the only species of Bassaricyon found east of the Andes. Bassaricyon alleni has a wide distribution in forests on the eastern slopes of the Andes and in lowland forests east of the Andes, with records from forested areas of Venezuela (Thomas 1920, Handley 1976, Bisbal 1989, 1993, Ochoa et al. 1993, Linares 1998, BMNH, USNM), Guyana (Pocock 1921a, Lim and Engstrom 2005, ROM), eastern Colombia (Thomas 1927, Donegan and Salaman 1999, AMNH, BMNH, USNM), eastern Ecuador (Thomas 1880, 1920, Schulenberg and Aubrey 1997, Pitman et al. 2002, Tirira 2007, Borman et al. 2007, Alverson et al. 2008, Pinto and Tirira 2011b, BMNH, EPN, FMNH, MCZ, QCAZ), eastern Peru (Thomas 1920, Grimwood 1969, Patton et al. 1982, Terborgh et al. 1984, Aquino and Encarnación 1986, Janson and Emmons 1990, Woodman et al. 1991, Pacheco et al. 1993, Pitman et al. 2003, 2004, Emmons et al. 1994a, 1994b, Emmons and Romo 1994, Boddicker 1997, Emmons 2001, Rodríguez and Amanzo 2001, Emmons et al. 2001, Vriesendorp et al. 2004, Alverson et al. 2008, Gilmore et al. 2010, BMNH, FMNH, MVZ, UMMZ, USNM, ZMB), northwestern Bolivia (Crespo 1959, Emmons 1991, Redford and Stearman 1993, Anderson 1997, Alverson et al. 2000, 2003, Alverson 2003, Ríos-Uzeda and Arispe 2010), and western Brazil (Calouro 1999, Kays and Russell 2001, Vaz 2004, Oliveira 2009, Magalhães-Pinto et al. 2009, Sampaio et al. 2010). In Guyana, Bassaricyon alleni is recorded only from two specimens, the type of beddardi (Pocock 1921a, see above) and a specimen from Iwokrama Forest (Lim and Engstrom 2005, at ROM); there are no records to date from either Suriname or French Guiana, where it might be expected to occur (Tate 1939, Husson 1978, Voss et al. 2001, Lim et al. 2005). In Brazil, the only firm records are from southwestern Amazonia (the states of Amazonas and Acre) (Calouro 1999, Kays and Russell 2001, Vaz 2004, Oliveira 2009, Magalhães-Pinto et al. 2009, Sampaio et al. 2010), though it is likely to occur also in Roraima and Pará (Figures 11–12). Brazilian Amazonian records of olingos from the state of Roraima, as “Bassaricyon beddardi” (Mendes Pontes and Chivers 2002, Mendes Pontes et al. 2002, Mendes Pontes 2004, 2009, Cheida et al. 2006), are thus far apparently based on misidentifications of kinkajous, Potos (Sampaio et al. 2011). The elevational range of Bassaricyon alleni as documented by museum specimens extends from sea level to 2000 m. The great majority of records originate from lowland forests below 1000 m, but specimens from Ecuador and Peru (especially from Chanchamayo) have been collected from 1100 to 2000 m (specimens at BMNH, FMNH, USNM). It seems likely that the distribution of Bassaricyon alleni extends higher on the eastern slopes of the Andes than that of Bassaricyon medius does on the western slopes because of the apparent absence of Bassaricyon neblina on the eastern versant of the Andes.