The red-billed emerald (Chlorostilbon gibsoni) is a species of hummingbird in the Trochilidae family. Formerly it was considered as part of the species C. mellisugus, blue-tailed emerald. As considered here, it does not include C. melanorhynchus, (western emerald), of west Colombia and Ecuador, which is sometimes considered conspecific. It is found in Colombia and Venezuela. Its natural habitats are subtropical or tropical dry forests, subtropical or tropical dry shrubland, and heavily degraded former forest.