"Banksia prionotes" grows as a tree up to high in southern parts of its distribution, but in northern parts it is usually a shorter tree or spreading shrub, reaching about in height; it diminishes in size as the climate becomes warmer and drier further north. It has thin, mottled grey, smooth or grooved bark, and tomentose young stems. The alternate dull green leaves are long, and wide, with toothed leaf margins made up of triangular lobes, and often a wavy surface.