The Rufous-naped Greenlet has a small range estimated at 23,700 km2 (BirdLife International 2011). It occurs in the Serranía del Perijá on the Venezuela-Colombia border, throughout the Andes of Colombia and on the east slope of the Andes in northern Ecuador. Its elevational center of abundance lies in the upper foothills and lower subtropics (Hilty and Brown 1986, Renhifo 1999). The species occurs chiefly from 1000-2100 m, but has been reported as low as 450 m on the Venezuelan side of the Serranía del Perijá (Ridgely and Tudor 1989). Rufous-naped Greenlet often has been described as uncommon and patchily distributed (e. g. Parker et al. 1996) but may be more common and widespread than previously realized, especially in Colombia (Cuervo et al. 2008).
In Venezuela, the Rufous-naped Greenlet ranges from 450-2000 m in the Seranía del Perijá and in Zulia from Cerro Alto del Cedro to the upper Río Negro drainage at Barranquilla and Cerro Mashirampé (Hilty 2003). There are many specimen records for the northeast side of the Serranía del Perijá (Hilty 2003).
The worldwide distribution of Rufous-naped Greenlet is centered in Colombia, where it is found throughout the western, central, and eastern cordilleras of the Andes (perhaps somewhat locally) and in the Serranía del Perijá (Hilty and Brown 1986, McMullan et al. 2010).
The Rufous-naped Greenlet is uncommon and local in northern Ecuador (Ridgely and Greenfield 2001a). Records range from 900-1400 m in the foothills and lower subtropics on the east slope of the Andes in western Napo (Ridgely and Greenfield 2001a). There are specimens from the 1920s and specimens and sight records from the 1990s from the lower slopes of Volcán de Sumaco (Ridgely and Greenfield 2001a). A specimen and some sight records from the 1990s also exist for the area north of Archidona on the road to Loreto (Ridgely and Greenfield 2001a). Also reported in Pastaza (Brewer 2010).