A telephone system comprising a plurality of telephone terminals is provided. The telephone system includes a switching device connected to the telephone terminals via a communication network, and a server device connected to the communication network. The switching device includes a transfer section for transferring a call to a telephone terminal in which a transfer function is set therein to a telephone terminal at a transfer destination. Also, the server device includes a monitor section for monitoring a log-in/log-out state of a user for each of the plurality of telephone terminals. The server also includes a releasing section for releasing the setting of the transfer function on the basis of the result of the monitoring when an operation to the telephone terminal with the transfer function set therein by a log-in user satisfies a defined condition.