A trailer coupling for a towing vehicle, having a coupling carrier, which includes, in particular, a coupling arm and at whose free end a coupling body, in particular, a coupling ball is arranged for connecting a trailer, and which coupling carrier is fixedly or movably arranged on a mount which is or can be attached to the towing vehicle, and having a sensor arrangement which has at least one sensor and has the purpose of sensing a traction force and/or thrust force which can be caused by a traction load acting on the coupling element during a traction operation of the trailer and of outputting a force signal representing the traction force and/or thrust force, and having an evaluation device for determining a trailer mass value of the trailer on the basis of the force signal.