South-eastern Brazil (north to Minas Gerais and Espírito Santo), Uruguay and north-eastern Argentina (Misiones south to Buenos Aires); southern populations winter north to south-central Brazil (southern Mato Grosso) and eastern Paraguay.
 
Population
Estimated population is unknown (2010).
Blue-billed Black Tyrant (Knipolegus cyanirostris) [XC45194]
by Marco Cruz from Estancia El Potrero (limite Norte), Gualeguaychu_Entre Rios, Argentina (call)
Blue-billed Black Tyrant (Knipolegus cyanirostris) [XC205707]
by Guilherme de Melo Becher from S\u00e3o Jos\u00e9 dos Campos-S\u00e3o Paulo, Brazil (call)