A mid-sized honeyeater at 16.5–17.5 cm (6.5–7 in) in length, it is olive-brown above and pale grey-brown below, with a black head, nape and throat, a pale blue to off-white patch over the eye, and a white crescent on the nape. Juveniles have brownish crowns, lemon-tinged nape, and an orange base of bill. Its call is a loud cheep cheep, or a churring.
The strong-billed honeyeater is found in mature forest with large trees, such as Eucalyptus regnans and E. delegatensis. Its diet is principally insects and various other invertebrates, which it hunts on tree trunks, supplemented by nectar and fallen fruit. Although both species are widespread in Tasmania, the Strong-billed rarely overlaps in site and foraging with the black-headed honeyeater.
Strong-billed honeyeaters may nest from September to January, breeding once or twice during this time. The nest is a thick-walled bowl of grasses and bits of bark in the fork of a tall tree, usually a eucalypt. Two or three eggs are laid, 22 x 17 mm in size, and shiny, buff-pink, sparsely spotted with red-brown.