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) [XC276372]
by Jonas Nilsson from Pichincha: Tandayapa ridge 3 km SSW Tandayapa, Ecuador (song)
Ashy-headed Tyrannulet (Phyllomyias cinereiceps) [XC61397]
by Charlie Vogt from Caba\u00f1as San Isidro, Cosanga, Napo, Ecuador (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.