Image: Traffic © Jetta Productions, Brand X Pictures, Getty Images

If only you could top off your car's cheap insurance the next time you were in Arizona.

Bullhead City, Ariz., is the least expensive town in the U.S. to buy car insurance. A 40-year-old male with a clean driving record in a 2012 Honda Accord would pay $730 a year, according to a new CarInsurance.com analysis of insurance rates in every U.S. ZIP code. For each town, we averaged insurance rates for all ZIP codes (most towns contain more than one) to find the most and least expensive places to buy car insurance.

That Bullhead City driver could:

  • Move a couple of miles to Laughlin, Nev., just across the Colorado River, and watch his rates zoom 70%, to $1,280 a year.
  • Head to New Orleans, where moving across town could make rates rise by 33%, or $872.
  • Try Manhattan, where within the 24 square miles of the island, the same driver in the same car could pay as little as $1,772 or as much as $2,847.

The most expensive town to buy car insurance in the U.S. is Highland Park, Mich., where the Accord driver would pay an astounding $4,214 a year. That's without any accidents, DUIs, speeding tickets or bad credit. (Use CarInsurance.com's "Nosy Neighbor" tool to compare average rates anywhere in the country.)

 
10 least expensive areas to insure a car
CityNotableAverage rate
1. Bullhead City, Ariz.On the Colorado River, opposite the casino destination of Laughlin, Nev.$730
2. Chloride, Ariz.The oldest continuously inhabited mining town in Arizona$731
3. Oatman, Ariz.Clark Gable and Carole Lombard honeymooned here, on the old U.S. Route 66$731
4. Pine Point, MaineKnown for lighthouses, lobster and beaches$733
5. West Scarborough, MaineWoodsy area of Scarborough, split by the Nonesuch River$733
6. Lake Havasu City, Ariz.Reassembled London Bridge, Arizona's second-largest tourist attraction$734
7. Cumberland Foreside, MainePortland suburb; "foreside" means it's on the beach$735
8. Amity, MaineMoose country; 2011 population: 186$736
9. Ashland, Maine"Crossroads of the Maine North Woods"$736
10. Blaine, MaineNamed for then-Speaker of the House James G. Blaine$736
 
10 most expensive areas to insure a car
CityNotableAverage rate
1. Highland Park, Mich.Home of the first Ford assembly line$4,214
2. Hamtramck, Mich.Along with No. 1 Highland Park, surrounded by Detroit$3,953
3. Fort Hamilton, N.Y.In the shadow of the Verrazano-Narrows Bridge$3,947
4. Brooklyn, N.Y.The most populous of the five New York boroughs$3,819
5. DetroitKnown at its height as "the Paris of the West"$3,709
6. Grosse Pointe Park, Mich.Tony suburb just east of Detroit$3,504
7. Bronx, N.Y.Home of the New York Yankees and the Bronx Zoo$3,443
8. Allison, TexasAtop a gas field known as the world's largest producer of helium$3,385
9. St. Albans, N.Y.Once home to CountBasie and Lena Horne$3,233
10. Springfield Gardens, N.Y.Just north of John F. Kennedy International Airport$3,213

It's all about the insurance claims

If you live in a particular ZIP code, your rate starts with that ZIP's base insurance rate -- whether your home is a mansion or a hovel.

Insurance companies group ZIP codes into different risk categories based on the number and severity of claims. "Territorial rating," as the practice is known, is used to produce a base rate that is the starting point for anyone seeking insurance coverage in most states.

A few states limit the use of territories as a primary rating factor. California, for example, requires insurance companies to calculate rates based on driving records and miles driven before considering location. But there's no getting around the impact of a high-risk address. Auto insurance rates in Los Angeles are 150% higher than those a hundred miles north in Santa Barbara.

"The differences in risk are pretty sizable," says Pete Moraga, a spokesman for the nonprofit Insurance Information Network of California. "Santa Barbara doesn't have the traffic or theft or vandalism that Los Angeles does."

Critics of territorial pricing say the poor are penalized for their addresses rather than for their driving history.

"I don't think any consumer would consider it fair that your address matters more than your driving record," says Mark Savage, a staff attorney for Consumers Union, which successfully pushed California regulators to emphasize driving experience, miles driven and driving record over ZIP code.

If all location-based rates were eliminated, Moraga says, those currently paying the least would face rising premiums. "It's a balancing act," he says. "Insurance is all about pricing risk fairly so that those with higher risk are paying what they should."

More from CarInsurance.com: