Bolivia, Brazil, Colombia, Ecuador, French Guiana, Peru, Suriname, Venezuela.
South-eastern Colombia (southern from Meta and Vaupés), southern Venezuela (Amazonas, southern Bolívar), Surinam and French Guiana south to Amazonian Brazil (south to northern Rondônia and south-western Pará), eastern Ecuador, eastern Peru and north-western Bolivia (Pando, extreme north-western La Paz).
 
Population
Estimated population is unknown (2010).
Rufous-tailed Xenops (Microxenops milleri) [XC592975]
by Michael Hurben from Rio Javar\u00ed, AM. Reserva Natural Palmar\u00ed, Brazil (song)
Rufous-tailed Xenops (Microxenops milleri) [XC23777]
by Alexandre Renaudier from Heath River Wildlife Center, Rio Heath, La Paz, Bolivia (song)
Subspecies
No subspecies.
Formerly placed in monotypic genus Microxenops. Differs from current congeners in lacking laterally compressed, wedge-shaped bill, black in tail and pale malar mark, also in leg colour, but shares with them a conspicuous wingband.