Black redstart bird is similar in size and shape to the Redstart, also perching upright and shivering its rusty-red tail. The black redstart bird (male) is charcoal-grey, with blacker face and underparts, and with a prominent white wing-patch on the secondaries, visible on the closed wing. The female is sooty grey-brown above and below, with a less obvious pale eyering than Redstart. In fresh plumage it shows fine silvery edges to the wing feathers.
Black redstart bird is a rare and localized breeder in Britain, but not uncommon on the continent. Resident in the more temperate parts of western Europe, it is otherwise a summer migrant and winters mainly around the Mediterranean. Black redstart bird is found from uplands to lowland towns and cities, favouring rocky and craggy terrain with bushes, industrial areas, chimneys, church towers and marginal urban areas with rank weedy growths, where it nests in a crevice or cavity in rocks, walls, roofs etc.
The calls of black redstart bird follow a similar pattern to those of its close relative, but it has a higher-pitched "seep" or "iisp" than the Redstart and also a harder and 'stonier' "teck'teck'teck'teck". The calls are often combined into a "iisp'teck'teck'teck" when the bird is more anxious. The song is a rather high-pitched phrase, often sung at first light from a conspicuous high perch. It is longer than the Redstart's song, averaging 3.5-5 seconds, and comprises three clearly separate parts. Black redstart bird is introduced with a rattle of sweet notes followed by a pause, then a curious quiet metallic scrunching and squishing noise, likened to a handful of ball bearings being shaken together, then a final flourish of three or four clearer rising notes, such as "eee'tyu'tyu'tyu'tyu .. .khxkhxkhxkhx tyu-che ch'chew". On some occasions only the introductory notes are heard.