An electrical plug-in connector for differential signal transmission, having an external conductor contact element, a dielectric and at least one internal conductor contact element pair for differential signal transmission. The dielectric extends along a longitudinal axis through the external conductor contact element. The internal conductor contact element pair has a first internal conductor contact element and a second internal conductor contact element which extend along the longitudinal axis through the dielectric. The external conductor contact element and/or the dielectric have a compensation geometry in order to compensate for an asymmetry of the internal conductor contact element pair with respect to the longitudinal axis. As an alternative or in addition, it is provided that the internal conductor contact element pair has a compensation geometry in order to compensate for an asymmetry of the external conductor contact element and/or of the dielectric with respect to the longitudinal axis.