The song of Spot-tailed Nightjar is described as "a high, passerine-like t-seet' or t-seeit', at times varied to t'tsuwee or t't'-sweee" (Howell and Webb 1995); as "a high, thin pit-suueét" (Hilty 2003); and as "a high lisping "tip-SEEEUUEEET" (Lane, in Schulenberg et al. 2010). This song is not necessarily loud, but carries for a long distance (Howell and Webb 1995, Hilty 2003). In Mexico the song of Spot-tailed Nightjar is "not always repeated incessantly as in other species" of nightjars (Howell and Webb 1995), although in Venezuela it is given "over and over at [a] rate of 1/1-3 sec but only for [a] short period when breeding (Mar?)", and in Bolivia, when breeding, the song may be given "almost nonstop for [hours] starting just after dusk" (Hilty 2003).
For a representative audio recording with sonogram, see audio
Calls of Spot-tailed Nightjar include "a rapid t-seet t-seet t-seet t-seet', an accelerating t-seet seet-seet, and a shriller, slightly wailing seeeu or see-ee-eeii in flight, which may be accompanied by a triple wing flutter, futt-a-futt or flut-flut-flut" (Howell and Webb 1995; see also Zimmerman 1957).