Crimson-rumped toucanets are mostly green in color and, as the name implies, have a red rump. They are somewhat darker and have a bronze tint above. The blue-green tail has some reddish-brown tips. The patch at the base of the mandible, area around the eyes and broad band across the breast are blue. The long, curved beak is reddish-brown and black, with a vertical white stripe at the base. Eye skin is brown and the iris is dark.