The southern school whiting has a very similar profile to other members of the genus "Sillago", with a slightly compressed, elongate body tapering toward the terminal mouth. The dorsal fin is moderately arched, while the ventral profile is straight. The species is known to grow to a maximum size of 33 cm and around 0.3 kg weight. The colouration of the species is also very similar to a number of other "Sillago" species which have an overlapping distribution, and in most circumstances, a more detailed analysis must be done to determine the species.