A connector assembly includes a contact module, signal contacts, and a ground contact. The contact module includes a dielectric body with mating and mounting edges and corresponding opposite back edges. The signal contacts are held within the contact module. The signal contacts include mating and mounting ends that protrude from the mating and mounting edges of the contact module, respectively. The signal contacts are arranged in a differential pair to convey differential signals. The ground contact is coupled to the contact module and includes mating and mounting ends that protrude from the mating and mounting edges of the contact module, respectively. The ground contact runs alongside the back edges of the contact module from the mounting edge to the mating edge.