No. 4: Idaho
Cost: $2,001 per year (10 percent below the national average)
Insurance premiums tend to be cheaper in Idaho, making the Gem State one of the cheapest for car owners in the nation. It's also the only non-Midwestern state to crack the top five.
The average cost of insuring a car in Idaho has been shrinking, according to National Association of Insurance Commissioners data, falling from $677 in 2007 to $642 in 2011. However, auto repair costs are slightly more expensive in Idaho than the national average. CarMD estimates that the typical Idaho driver pays $349 per year.