Song: Published phonetic descriptions of Rufous-naped Greenlet song include: A fast, complex wa-chee-ra-dit'it, rising in frequency (Hilty 2003); a musical, warbled wacheera-ditit rising in pitch (Hilty and Brown 1986); a fast, warbled wacheera-ditit (Ridgely and Tudor 1989); a characteristically doubled deedidoreét (Ridgely and Tudor 2009); and a fast, repeated cheedodoweédidideét (Ridgely and Greenfield 2001b). The song frequently has been described as weak (Hilty 2003, Hilty and Brown 1986, Ridgely and Tudor 1989), but in Antioquia, Colombia the song was observed to be quite loud and easily recognized from a distance (D. Slager, personal observation).
Singing phenology: Singing males reported on 23 April and 1 September at 1800 m on the west slope of the Andes above Cali, Valle del Cauca, Colombia (Miller 1963). Singing males commonly heard from 10 January to 22 February 2011 at three shade coffee plantations in Antioquia, Colombia between 1500-1700 m (D. Slager personal observation).
Calls: Rufous-naped Greenlets also give a descending series of 3-5 loud, harsh, scolding notes (D. Slager, personal observation, Antioquia, Colombia). An example of this call type can be heard at position 18 s in Macaulay Library Audio 78543.