PURPOSE: To accurately impose a bill of a talking charge onto a caller making connection of public line-private line-public line by connecting a charging device executing totalization processing by each ID number to each PBX.

CONSTITUTION: A terminal equipment 3a dials a destination number with an ID number added thereto and makes talking with a terminal equipment 3b. When the talking is finished, a PBX 2c detecting it, the PBX 2c generates and stores talking detailed information with an ID number with respect to the talking between the PBXs 2c, 2d. Similarly a PBX 2d generates and stores talking detailed information with an ID number with respect to the talking between the PBX 2d and a terminal equipment 3b. Charging devices 6a, 6b receive each detailed information independently and collects the talking charge by ID and generates an ID dependent talking charge daily report. Thus, the charging result of each talking is not returned to other PBX and the talking charge is correctly imposed on the caller.