It has a black cap and throat, gray back and pale sides. Though often described as a slightly larger and paler version of the more common boreal chickadee, the Siberian tit superficially looks like a black-capped with a grayish brown cap. Its white cheek patches are larger than those of the other four species. A white eyebrow stripe sets it apart from other chickadees. The calls of the boreal and mountain are similar, but the boreal's is slower and more nasal, and the mountain's is buzzier.
Chickadees nest in cavities.
They may excavate a nest for themselves in well-rotted wood or use an old woodpecker hole, natural cavity, or nest box. The nest at the bottom of the cavity is lined with plant fibers, animal hair, moss, and other soft materials. Six to eight eggs are the normal clutch. Young birds remain with their parents for about 3 weeks after fledging and then, as defense of breeding territories by the parents diminishes, the young disperse rapidly from their birthplaces. The small flocks of chickadees commonly seen from late summer through winter are generally not composed of family groups but of several adult pairs and unrelated juveniles.