Bolivia, Brazil, Colombia, Ecuador, French Guiana, Guyana, Peru, Suriname, Trinidad and Tobago, Venezuela.
Eastern Colombia (southern from Meta and Vaupés), eastern and southern Venezuela (south-eastern Sucre south to Delta Amacuro, Bolívar and Amazonas), Trinidad and the Guianas south to eastern Ecuador (primarily R Napo and R Aguarico, but certainly more widespread), eastern Peru (Loreto, Ucayali, recorded also Madre de Dios), extreme north-western Bolivia (Pando area), and Amazonian Brazil (east to Maranhío, south to Rondônia, southern Mato Grosso, Goiás and Tocantins).
 
Population
Estimated population is unknown (2010).
Sulphury Flycatcher (Tyrannopsis sulphurea) [XC433305]
by Juan D\u00edaz Alv\u00e1n from Roura, Beaus\u00e9jour, French Guiana (call)
Sulphury Flycatcher (Tyrannopsis sulphurea) [XC525711]
by Mauricio \u00c1lvarez-Rebolledo (Colecci\u00f3n de Sonidos Ambientales - Instituto Humboldt) from PNN Chiribiquete, cunar\u00e9- Am\u00fa, Colombia (?)
Subspecies
No subspecies.
Long considered closely related to Myiozetetes on grounds of plumage. More recent evidence relating primarily to syringeal morphology, nest architecture and molecular-sequence data indicates close affinity with, instead, Megarynchus. Molecular data also provide conflicting but fairly weak evidence for the two being either the sister-group to Conopias, or basal to a group including Conopias as sister to a well-supported clade containing Empidonomus, Griseotyrannus and Tyrannus, but additional sequence data necessary in order to resolve true affinities among these taxa.