A communication apparatus including: a requiring section which transmits a requirement for establishing a state in which and the communication apparatus and a first communication apparatus are communicable with each other via an internet line, to the first communication apparatus via the internet line; a communication establishing section which establishes the state; a calling section which transmits a dial signal to an exchanger via the telephone line and calls a to-be-called apparatus, when the communication establishing section has established the state; a notifying section which transmits a notification about calling of the communication apparatus, to the first communication apparatus via the internet line after the calling section has called; a receiving section which receives an acknowledgment signal transmitted via the internet line from the first communication apparatus having received the notification; and a communication controlling section which controls the communication with the to-be-called apparatus via the telephone line.