The Slaty Spinetail is common in a variety of open woodland and shrubby habitats in the tropical and subtropical zones (200-3300m), ranging from the northern coast of Honduras to southwest Ecuador. It is often found foraging in family groups or pairs in low, dense vegetation. It has a uniformly dark gray body with deep rufous wing coverts and a rufous crown, extending from behind the forehead to the nape. The four subspecies recognized are separated both geographically and altitudinally. Brachyura is found in northern Colombia (mostly below 300m) and has a deep chestnut crown and a paler gray supercilium. Caucae is found mostly above 1,000m central Colombia is paler overall. Griseonucha of southwest Ecuador is darker overall with a silvery throat and some white in the belly. Nigrofumosa is found primarily above 1,000m in western Ecuador and western Colombia, and is similar to griseonucha but with a dark throat.