Abstract: The invention relates to a flow measurement method comprising a generation of successive cycles, each cycle comprising: —a step (35) in which an ultrasonic wave is emitted by a first ultrasonic transducer; —a step (36) in which said ultrasonic wave is received by a second ultrasonic transducer; and —a step (37) in which a propagation time of said ultrasonic wave from the first ultrasonic transducer to the second ultrasonic transducer is measured, the method being characterised in that a given cycle is separated from the preceding cycle by an intercycle duration, and in that a flow rate of the fluid is calculated from a difference between the propagation time of the given cycle and an average of the propagation time measured for the preceding cycle and that measured for the cycle following said given cycle.