The grey-capped warbler is found in Burundi, Democratic Republic of the Congo, Kenya, Rwanda, South Sudan, Tanzania, and Uganda.

It is a large, chunky, thin-tailed-warbler with a distinctive grey cap, a black band around its head, and a chestnut throat wrapping its neck.

Grey-capped warblers maintain a diet of insects and other invertebrates, including caterpillars, moths, grasshoppers, and mantids.

It is typically chunky and thin-tailed with a distinctive grey cap, a black band around the head, and a chestnut throat with rump feathers that are long and lax.

It is found in dense undergrowth, scrub, and creepers, usually in damp areas along forest edges, seeps, or riparian strips, as well as around well-planted gardens.

It is joined by a large variety of frugivorous and insectivorous species attracted to stands of fruiting Euclea divinorum trees in Tanzania.

The grey-capped warbler breeds during rains: Mar-Jun and Oct–Nov in Sudan and DR Congo, Apr-May in Uganda, and May–Aug and Nov–Jan in Kenya.

The nest is an untidy, ball-shaped structure, with a side entrance and protruding porch (up to 8 cm long) and platform (2·5 cm), made of long strips of fibrous vegetation and leaves, woven together and lined with moss, spider webs, rootlets, feathers and plant down, suspended from a thin branch or creeper inside dense vegetation, sometimes slung between two saplings, usually, 1–3 m (rarely 5 m) up, often over water, where it resembles debris lodged in the overhanging branch.