Disclosed is an ultraviolet light sanitation device for retail checkout counter conveyor belts with a UV-C light source, a housing, and a mount. The UV-C light source is internally positioned at an apex end of the housing opposite a treatment opening of the housing, where a conveyor belt of a retail checkout counter is exposed to the UV-C light source through the treatment opening in order to sanitize the conveyor belt through germicidal irradiation by the UV-C light source. The mount connects the housing to a retail checkout counter such that the treatment opening is positioned adjacent to the conveyor belt, either adjacent to an underside of the conveyor belt within a conveyor cabinet of the retail checkout counter, or external to and atop the conveyor cabinet.