Belize, Bolivia, Brazil, Canada, Colombia, Costa Rica, Ecuador, El Salvador, Guatemala, Honduras, Mexico, Nicaragua, Panama, Peru, USA (B).
Breeds south-western USA (mountains in southern Arizona), Mexico (southern on both slopes from Sonora, eastern Nuevo León and Tamaulipas), Guatemala and Belize south to Costa Rica. Winters eastern Ecuador, eastern Peru, extreme western Brazil (along R Juruá, in Acre) and Bolivia (south to Cochabamba and western Santa Cruz).
 
Population
Estimated population is 2,000,000 (2010).
Sulphur-bellied Flycatcher (Myiodynastes luteiventris) [XC274804]
by Manuel Grosselet from Sierra de Miahuatl\u00e1n--La Soledad, Oaxaca, Mexico (song)
Sulphur-bellied Flycatcher (Myiodynastes luteiventris) [XC429401]
by Oscar Campbell from Chiquil\u00e1, L\u00e1zaro C\u00e1rdenas Municipality, Quintana Roo, Mexico (song)
Subspecies
No subspecies.
Affinities of genus uncertain. For long hypothesized as being closest to Conopias, largely on basis of similar hole-nesting tendencies. Genus probably monophyletic, although this only weakly supported by recent analyses of molecular-sequence data (likely due to inappropriate markers for the apparently long branches and deep level of divergence within genus). Results of separate analyses of plumage/syringeal morphology and molecular data were not completely congruent, but evidence strongly suggests that present species is sister to Streaked Flycatcher (Myiodynastes maculatus), and that the two are sister-group to a clade consisting of Golden-bellied Flycatcher (Myiodynastes hemichrysus) and Golden-crowned Flycatcher (Myiodynastes chrysocephalus). Specimens southern from Guatemala evidently have heavier streaking on chest and throat and smaller bill than birds from Mexico, but differences deemed too inconstant to warrant subspecific separation.