South-eastern Brazil from central Bahia (Chapada Diamantina) south to northern Rio Grande do Sul, also adjacent eastern Paraguay (Alto Paraná, Itapúa) and north-eastern Argentina (Misiones, north-eastern Corrientes).
 
Population
Estimated population is unknown (2010).
Black-billed Scythebill (Campylorhamphus falcularius) [XC419155]
by Caio Brito from Monte Alegre, Tel\u00eamaco Borba, Paran\u00e1, Brazil (alarm call)
Black-billed Scythebill (Campylorhamphus falcularius) [XC294727]
by Jerome Fischer from Doutor Pedrinho, Doutor Pedrinho, Santa Catarina, Brazil (song)
Subspecies
No subspecies.
Sometimes thought to form a superspecies with Red-billed Scythebill (Campylorhamphus trochilirostris). Regarded by some authors as conspecific, an arrangement disputed by most. Close relationship with Curve-billed Scythebill (Campylorhamphus procurvoides) is also suggested.