South-eastern Brazil (southern Mato Grosso do Sul east to Espíritu Santo, south to Rio Grande do Sul), eastern Paraguay and northern Argentina (Misiones).
 
Population
Estimated population is unknown (2010).
Rufous-crowned Greenlet (Hylophilus poicilotis) [XC30467]
by Adrian Eisen Rupp from Rio da Prata, Veran\u00f3polis, Rio Grande do Sul, Brazil (song)
Rufous-crowned Greenlet (Hylophilus poicilotis) [XC723967]
by Jacob Wijpkema from San Ramon (near San Ram\u00f3n), Mamore, Beni Department, Bolivia (call, duet, song, subsong)
Subspecies
No subspecies.
Formerly treated as conspecific with Grey-eyed Greenlet (Hylophilus amaurocephalus), with which partly sympatric, but appears to be clearly differentiated by plumage, eye colour, vocalizations and habitat preference. Previously reported hybridization between the two explained as being due to presence of a "residual cline" that reflects geographical variation of the ancestor.