Allocating first transmitters of a tire monitoring system, especially of a tire-pressure monitoring system having a wheel unit comprising a sensor, a first transmitter, which can be triggered, and a sending antenna on each of N wheels arranged on L axles of a vehicle according to a predetermined axle formula, further having receiving antenna on the vehicle body associated to the first transmitters and an electronic receiver and evaluation system, connected to receiving antenna by allocating an identifier characteristic of a particular wheel to its respective first transmitter, by emitting data telegrams, which contain the identifier, in response to a triggering action of second transmitters, and passing on such data telegrams to the central electronic receiver and evaluation system. The number n of the trigger transmitters is smaller than the number A of the axle positions, that each axle position is associated to a triggering range of n trigger transmitters.