Abstract: A signaling device for being coupled to a mailbox of the type having a cantelievered tongue section defined below the mailbox door hinge. A snap-type single pole single throw (SPST) push on push off action switch is coupled to the base of the mailbox adjacent to the tongue section of the door for generating a first signal responsive to the operative communication between the tongue section of the door as the door is opened. An electrical circuit is coupled to the switch for generating a sensory perceptible signal responsive to receiving the first signal from the switch. The switch is mounted on a generally U-shaped bracket which may be deformable as the switch is being actuated, thereby reducing the possiblity of damage to the switch as the door is opened.