A receptacle connector includes a housing having a mating interface for mating with a mating connector. Ground contacts are held by the housing. The ground contacts include ground mating segments arranged along the mating interface of the housing for mating with ground terminals of the mating connector. The ground mating segments of the ground contacts include ground mating surfaces configured to engage the ground terminals. The ground mating surfaces of the ground mating segments extending within at least one ground plane. Signal contacts are held by the housing. The signal contacts include signal mating segments arranged along the mating interface of the housing for mating with signal terminals of the mating connector. The signal mating segments of the signal contacts include signal mating surfaces configured to engage the signal terminals. The signal mating surfaces of the signal contacts extend within at least one signal plane that extends parallel to and is spaced apart from the at least one ground plane.