The lesser house fly is grey black with three indistinct black stripes along the thorax. Female have grey oval abdomen; males have narrower abdomen with pale yellow patches. When at rest they hold their wings over the back forming a narrow V-shape (compared to the common house fly which forms a broader V-shape). The legs are black and the halteres yellow. It is commonly seen in the house, and has distinctive flight pattern where it darts around in square or triangular patterns in a shaft of light or under a light fitting.