An electrical connector defining a receiving cavity for receiving a corresponding plug includes an insulative housing and a number of contacts retained in the insulative housing. The contacts include a number of first contacts which are arranged in a row along a transverse direction of the insulative housing. The first contacts include two pairs of differential signal contacts and a grounding contact between said two pairs of differential signal contacts. Each first contact has a contact portion extending into the receiving cavity, a tail portion extending out of the insulative housing and a connecting portion between the contact portion and the tail portion. The connecting portion of the grounding contact is wider than that of the differential signal contacts in the transverse direction.