Continued growth and development in the Puget Sound region combined with existing geographic limitations have resulted in a transportation network that is at or near capacity for many hours during every weekday. Single-occupancy vehicles (SOVs) remain the predominant mode of travel, despite a network of high-occupancy vehicle lanes and regional transit. Given this situation, considering alternative methods to regulate traffic flow is necessary, and the implementation of a regional congestion pricing system is one such option. Although widespread throughout the world, congestion pricing has only recently been implemented in the United States.