Many factors go into calculating insurance costs, and you can do a number of things to win lower rates:

• Get good grades: Insurance companies believe that good students make safer drivers, and students with high grades can receive discounts.
• Get a car with airbags: Airbags can save more than your neck. Because they significantly reduce the chance of major injuries, they can also mean lower insurance premiums.
• Get a sturdy car: Like airbags, sturdy cars mean fewer serious injuries, thus reducing insurance costs (and medical bills).
• Shop for a household discount: If both you and your spouse have a car, consider getting a single insurer--you may qualify for a household discount. The same may apply if you have children who drive. Some insurance companies will also provide discounts if you buy life and homeowner's policies with them, as well.
• Get married: Some insurance companies consider married people a lower risk than singles, and whether or not your spouse drives, you can get lower rates just for being married. Discounts vary from company to company and on a case-by-case basis.
• Maintain a good driving record: Many companies offer a discount for good driving, sometimes as much as 20 percent. You'll generally qualify if you've been with the same insurer for more than 36 months without filing a claim. By contrast, every time you get into an accident that's your fault, your insurance premiums increase--sometimes significantly--for up to five years or more. Even traffic violations, from speeding to running a stop sign, can send costs skyward for the same amount of time. So, you have a powerful incentive to drive safely and obey all traffic laws. If you've already racked up a spotty record, taking a defensive driving course could significantly reduce your rates. Ask your insurer about potential discounts and a list of approved programs.
• Drive less: Insurers will ask you how many miles you drive per year. The lower the number, the lower your rates. If you commute, you can expect to pay extra.
• Install a car alarm: If you have comprehensive auto insurance, you'll get lower rates if you install a car alarm. In fact, a car alarm could easily pay for itself over time through lower insurance rates.