Adults weigh from 29.5 to 40 g (1.04 to 1.41 oz) and are 16 to 18 cm (6.3 to 7.1 in) in length. The adult's upper parts are olive to black and the underparts yellow with an olive wash on the flanks. The sides of the head are black with a yellow crown stripe and throat. Juveniles are dark brown above and lighter brown below with a rufous crown.
The choco brushfinch is a year-round resident of Colombia's western Andes and western Ecuador. It inhabits open cloud forest and the undergrowth of openings in and edges of humid forest and secondary woodland. It is found primarily from 600 to 2,300 m (2,000 to 7,500 ft) though there are scattered records from lower and higher elevations.
Little is known about the choco brushfinch's diet. It is known to forage up to 10 m (33 ft) above ground, in contrast to many other brushfinches which forage mainly near the ground. It forages alone, in pairs, or as a member of a mixed-species flock.
Little is known about the species' nesting phenology as well. Observers have reported nest-building in Colombia in November, February, and May; eggs in April; and fledglings in June and July. A reported nest was a thick cup placed near the ground; it contained one white egg with dusky spots.