The invention relates to a shear-off screw (1) for fastening a conductor (2) of an electric cable in a connecting element (3) with a hollow-cylindrical threaded portion (5), in which the shearing off takes place when a predetermined torque (T) is exceeded and a pressure piece (7) arranged inside the threaded portion (5), wherein the pressure piece (7) has an axial excess length (AL) with respect to the threaded portion (5). The invention further relates to a method of fastening a conductor (2) of an electric cable in a connecting element (3) with a shear-off screw (1).