Call notes of the Gray-headed Tanager have been described as warbler- and hummingbird- like and include a sharp, high-pitched, unmusical chewt. These high-pitched calls can be difficult for predators to detect yet are transmitted poorly in the forest understory (Willis 1985). Call notes often are repeated at a rate of one note per second (Isler and Isler 1999). A possible alarm call may be a low-to-moderate rattle (Slud 1964, Isler and Isler 1999), often repeated several times (Willis 1985). Other calls include "a squeaky, high, thin tseet, often repeated 2-3 times [and] a high-pitched, thin chip or pit, sometimes repeated incessantly" (Costa Rica; Stiles and Skutch 1989); a schip alarm note (eastern Colombia; Hilty and Brown 1986); and a "high, sibilant, descending series 'swee-swee-swee-swee' " (Lane, in Schulenberg et al. 2007).
Only males sing (Willis 1985) and have been observed singing while foraging, nest building and perching, yet do this sparingly (Skutch 1989, Restall et al. 2007). Songs of the Gray-headed Tanager are a jumbled series of sputtering notes and described in the literature as high, buzzing notes (Ridgley and Tudor 1989, Isler and Isler 1999, Restall et al. 2006), yet Skutch (1954) described it as soft with a smooth flow. The song of the Gray-headed Tanager varies geographically (Isler and Isler 1989). The song in Costa Rica is described as "a high, thin, rather sibilant medley, whichis whichis whicheery whichis whichu', tsee tseep SEEUr tsp-tsp tseeur tsp-tsp seeur ts-suur, etc." (Stiles and Skutch 1989). In Aragua, northern Venezuela, the song is described as "a high, buzzy pzzzt-buzzt-buzzt-fzzzt" (Hilty 2003). The song in Peru is "a loud, strident series of jerky, ringing notes interspersed with high sibilant sounds, seeps, and chips" (Lane, in Schulenberg et al. 2007). In south central Brazil, the song is described as "a sequence of high whistles with 2nd part of stanza descending, tsee, tsee, tsee, tsi, tsi, tsi, tsi, tsi, tsi, sometimes more varied and prolonged" (Sick 1983).