Parking facilities are a critical part of a transportation system: vehicles are typically parked about 23 hours per day and require parking at each destination. These facilities impose various economic, social and environmental costs. This article estimates the number of parking spaces per vehicle, their costs and prices. This information is important for policy and planning analysis. Recent surveys indicate that North American communities typically average three to eight parking spaces per vehicle, including many seldom-used government-mandated spaces. Their annualized costs, including land, construction and operating expenses, typically range from about $600 for basic surface parking on inexpensive land to more than $5,000 for high-amenity structured parking. Overall, their costs are estimated to average about $1,000 annually per space or $5,000 per vehicle-year, totaling more than a trillion dollars per year in the U.S. For every dollar motorists spend on their vehicles somebody spends about a dollar on parking. Most parking costs are external, increasing taxes, rents and retail prices. This is economically inefficient and unfair since it increases total parking and traffic costs, and forces households that drive less than average to subsidize higher-mileage motorists. More efficient parking management could provide larger savings and benefits than previously recognized.