The song of the Flame-rumped Tanager is "a scolding chewp!" (Wetmore et al. 1984). The most common call note is composed of a low to moderate-pitched nasal anh or cha used in alarm or hostility and a high, hard ezzheet, which is probably a contact note (Isler and Isler 1987). Others include a hoarse zraa, rapid rattles of low pitched, wooden-sounding notes used in hostile encounters. A variety of harsh call notes have been described for both male and female (Ridgely and Tudor 1989) and the note from the female is exactly like the note from the female House Sparrow (Wetmore et al. 1984).
Dawn song is given only during the breeding season (Moynihan 1966) and consists of same phrase repeated kioo or klioo, uttered more frequently in Ramphocelus flammigerus icteronotus than in Ramphocelus flammigerus flammigerus (Ridgely and Greenfield 2001). The range of bisyllabic notes described includes tseee-yah, tseee-up, eee-ya and khee-zoo (Moynihan 1966). The male has a more musical dawn song, although rather simple and repetitious (Ridgely and Tudor 1989).