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) [XC271987]
by Jeremy Minns from Colakreek, Para, Suriname (call)
Sulphury Flycatcher (Tyrannopsis sulphurea) [XC91512]
by David Bradley y Sandra Valderrama from Portillo, S of Iberia, Madre de Dios, Peru (call)
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.