Trailer coupling with a sensor

The coupling (10) has a coupling body (15) comprising a counter bearing surface (28) for a closure element (21) of a traction coupler (16). The closure element is adjustable between closing and open positions and moved toward the counter bearing surface to lock the traction coupler at the coupling body in the closing position. The closure element is moved away from the counter bearing surface to release the traction coupler from the coupling body in the open position. A sensor arrangement (30) comprises a locking sensor (70) for recognizing a closing position of the closure element. The locking sensor is designed as a contactless optical, inductive and/or capacitive sensor. The coupling body is designed as a clutch ball. The traction coupler is designed as a traction ball joint.