A tailgate indicator light device comprises a sensor mounted adjacent an existing tailgate bolt configured to communicate wirelessly with an alert module. The alert module is capable of being mounted to a vehicle dashboard and comprises a plurality of illumination means. The sensor and module may be powered by the electrical system of the vehicle or a rechargeable battery. A USB port is disposed within the housing of the alert module. The device is configured to visually communicate to a user the open or closed status of the tailgate of a vehicle into which the device is installed.