Elachista modesta is a moth of the Elachistidae family. It is found in Greece (Lesbos and Rhodes) and Turkey. The wingspan is 8–8.2 millimetres (0.31–0.32 in) for males and 8-9.6 mm for females. The forewing ground colour is creamy white, variably irrorated by ochreous brown scales. The hindwings are dark grey above, with paler yellowishgrey fringe scales.