Burundi, Congo [The Democratic Republic of the], Kenya, Rwanda, Tanzania [United Republic of], Uganda, Zambia.
Locally in north-eastern and eastern DRCongo (north-eastern Uele and eastern Ituri, Kivu), south-western and south-eastern Uganda (Toro, western Ankole, Kigezi, and Sizibwa swamp), north, central and eastern Rwanda and central and eastern Burundi; also south-western Kenya (L Victoria, from Yala swamp south to Kisumu and Kendu Bay) and northern Zambia (R Luapula).
 
Population
Estimated population is unknown (2010).
White-winged Swamp Warbler (Bradypterus carpalis) [XC42862]
by Martin St-Michel from Kabaya Valley Papyrus Swamps, SE Rwanda, Rwanda (song)
White-winged Swamp Warbler (Bradypterus carpalis) [XC739441]
by Niall Perrins from Murchison falls National Park, Uganda (song)
Subspecies
No subspecies.
Perhaps allied to Little Rush-warbler (Bradypterus baboecala), which it resembles vocally. These two, together with Grauer's Swamp-Warbler (Bradypterus graueri) and Dja River Swamp-Warbler (Bradypterus grandis), make up a group of four swamp-dwelling Afrotropical species.