Andes in extreme south-western Venezuela (southern Táchira), Colombia (all three cordilleras), western and eastern Ecuador and eastern Peru (south to Cuzco).
 
Population
Estimated population is unknown (2010).
Ashy-headed Tyrannulet (Phyllomyias cinereiceps) [XC262946]
by Paul Coopmans from Pichincha: Mindo area, Ecuador (song, agitated song)
Ashy-headed Tyrannulet (Phyllomyias cinereiceps) [XC838848]
by Andrew Spencer from San Carlos District (near Cocachimba), Bongar\u00e1 Province, Amazonas, Peru (song)
Subspecies
No subspecies.
Genus as presently constituted may be polyphyletic. Anatomical evidence suggests that present species may be closest to Planalto Tyrannulet (Phyllomyias fasciatus) and Sooty-headed Tyrannulet (Phyllomyias griseiceps) and that all perhaps unrelated to others of genus, some or all of which possibly better placed in resurrected genus Tyranniscus. Was for long placed in latter.