PURPOSE: To confirm the communication charge during the communication by providing a limit charge registration list registering a limit charge for each terminal equipment or for each caller subscriber and a charge index table relating to a path up to a destination and using a call control section of an exchange to receive an alarm for the communication in excess of the limit charge.

CONSTITUTION: A limit time arithmetic section 25 receives a caller number and a limit charge from a call control section 22 and receives a caller number and a charging index from a charge index table 24, then the limit time is calculated by the limit charge and the charge index and the limit time is outputted to a comparison collation section 28 together with the caller number. A time measuring section 26 records the charge index from the charge index table 24 to the caller number, the measurement of the communication time is started by the reception of a reply signal of the call for each caller number and the measured communication time is outputted to the comparison collation section 28. Then the comparison collation section 28 stores the limit time received from the limit time arithmetic section 25 for each caller number and sends an alarm when the measured value received from the time measuring section 26 reaches the stored limit time. Thus, the charge is able to be confirmed during the communication.