Burundi, Congo [The Democratic Republic of the], Rwanda, Uganda.
Eastern DRCongo (highlands west of L Edward, south to Itombwe), south-western Uganda (Bwindi-Impenetrable Forest) and western Rwanda (Nyungwe Forest).
 
Population
Estimated population is unknown (2010).
Grauer's Warbler (Graueria vittata) [XC667518]
by Magnus Wadstein from Bwindi, Western Region, Uganda (call)
Grauer's Warbler (Graueria vittata) [XC105977]
by Brian Cox from Kahuzi-Biega National Park, Mount Bugulumiza, Congo (Democratic Republic) (song)
Subspecies
No subspecies.
Affinities uncertain. Often considered close to Macrosphenus, but bill shorter and stronger, a feature which has caused some authors to regard it as a babbler (Timaliidae). Barred underparts and build suggest possible close relationship with Calamonastes, in family Cisticolidae. Further research is required.