Confined to far south-eastern Australia, Tasmania, King Is and Flinders Is with outliers in the Mt Lofty Range and Kangaroo Island, S.A., Crescent Honeyeaters inhabit wet gullies densely vegetated with ferns and coarse sedges from high in alpine areas down to coastal heathlands. On Kangaroo Island they are widely spread through the mallee.

Crescent Honeyeaters breed as pairs in semi-permanent territories, those in the high country may be vacated in winter when some birds descend to lower altitudes. Females alone build the nest and incubate the eggs but both sexes feed the nestlings. Males actively defend the territories with loud two-note calls resembling the sound e-gypt.