To provide an electric device capable of clearly grasping a use start date by a user, and a method for managing the use start date of the electric device.

Prior to the shipping of the electric device 10, 1 is set to a data region for determination which lies in the region of a nonvolatile memory 13 in which a user cannot rewrite data. When the input of a control power source 11 by the user is detected by a control part 12, the control part refers to the data region for determination of the nonvolatile memory 13, and when 1 is set, calendar data by a calendar part 15 are set to a calendar region which lies in a region in which the user cannot rewrite data, and the data region for determination is reset to 0. When the data region for determination is 0, the region of the calendar data is not updated even when the control power source 11 is input.