Abstract: An electrically-heated insulated warming bag, in which the handheld unit of an ignition interlock device can be stored while not in use so that the handheld unit can be used on cold days without experiencing condensation problems, plugs into a cigarette lighter receptacle. The warming bag, which has resistive wire pattern sandwiched between an insulation layer and an inner lining layer, also has an outer cover which overlies the insulation layer. The stack, consisting of the outer cover, the insulation layer, the resistive wire pattern, and the inner lining layer, is folded over and sewn around the resulting perimeter to create the bag. One side, which is left open to provide entry to the interior of the bag, is sealable by means of hook and loop fastener strips, which are sewn to inside opposite edges of the opening. The bag may incorporate a thermostat to minimize power consumption.