South-eastern Brazil (southern from southern Goiás, southern Minas Gerais and southern Espírito Santo), eastern Paraguay (eastern from Paraguarí), north-eastern Argentina (Misiones, eastern Corrientes) and northern Uruguay.
 
Population
Estimated population is unknown (2010).
Grey-bellied Spinetail (Synallaxis cinerascens) [XC698134]
by Miguel Angelo Biz from RPPN Vale dos Ip\u00eas, Cl\u00e1udio, Minas Gerais, Brazil (song)
Grey-bellied Spinetail (Synallaxis cinerascens) [XC472267]
by Bernabe Lopez-Lanus from Pousada Para\u00edso, Taquaril - Petr\u00f3polis - RJ, Brazil (alarm call, song)