Elachista kilmunella is a moth of the Elachistidae family. It is found from northern Europe to the Alps and Hungary and from Ireland to Russia. The wingspan is 8–12 millimetres (0.31–0.47 in). Adults are on wing from May to August. The larvae feed on Carex riparia and Eriophorum vaginatum. They mine the leaves of their host plant. They are yellowish grey. Larvae can be found from April to July.