This species is 13 centimetres (5 in) long and weighs 11 grams (0.39 oz). The summer male Black-and-white Warbler is boldly streaked in black and white, and the bird has been described as a flying humbug. There are two white wing bars. Female and juvenile plumages are similar, but duller and less streaked. These birds feed on insects and spiders, and unlike other warblers, Black-and-white Warblers forage like a nuthatch, moving up and down tree trunks and along branches. The song is a high see wee-see wee-see wee-see wee-see wee-see, and the call is a hard tick.
Breeds in mature and second-growth deciduous and mixed forests. Winters in variety of habitats from disturbed areas to mature forests.