A coffee machine has a body, a dispensing unit, a conduit, a supply and heating device, a filter holder, fast coupling/uncoupling means to couple the filter holder under the conduit, a control unit, a presence sensor to detect the presence of the filter holder under the conduit, and a switch to enable the passage of electrical current towards the supply and heating device and towards the dispensing unit when the presence sensor detects that the filter holder is uncoupled from the fast coupling/uncoupling means. The control unit has a timer to manage the opening/closing of the switch.