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) [XC384737]
by Fernando Igor de Godoy from Parna Capara\u00f3, Alto Capara\u00f3, Minas Gerais, Brazil (call, song)
Black-billed Scythebill (Campylorhamphus falcularius) [XC733273]
by Mateus Gon\u00e7alves Santos from Sao Jose dos Campos, state of Sao Paulo, 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.