A telephone timing device adapted to be mounted on a desk or table telephone having a base unit and a telephone hand set, and having means for engaging the base unit of the telephone. In order to disable the telephone for a predetermined period of time, the hand set including the receiver and transmitter is lifted from the cradle of the phone, thereby permitting the switch on the base unit to close, and thereby disabling the phone with regard to incoming calls. A timing device is provided which may be set to a predetermined time, at which time a spring loaded bolt or plunger is released to engage and depress the switch plunger on the base unit and to open the switch, thereby reactivating the telephone for the reception of external calls.