Count 'em: 15 car insurance discounts

This post comes from Rob Berger at partner blog The Dough Roller.

Next to a root canal, paying for car insurance is about as painful as it gets. And the bill always seems to be an unpleasant surprise. Just when you think you've got the monthly budget under control, along comes a hefty six-month premium.

So I did some research into the common discounts that most car insurance companies offer. Some won't be much of a surprise, but there are some you may not know about. It's a good practice to check with your agent to make sure you're taking advantage of every discount for which you qualify.

Driving history and habits discounts

1. Safe driving discount. Discounts for safe driving take several forms. With some companies, you'll get a discount when you go without an accident for a number of years (typically four or five years). Some companies offer to lower your deductible $100 each year you're accident-free (Nationwide calls it the vanishing deductible). And in the case of Progressive, you can actually install a device (called the Progressive Snapshot) that monitors your driving. Based on the results, you may get a lower premium.

2. Low mileage discount. If you don't put a lot of miles on a vehicle, you may qualify for lower premiums. There's no standard mileage to qualify, although what I've seen typically requires no more than 12,000 miles per year. But the number varies, so you'll need to check with your insurance company.

3. Driving habits discount. There are a number of good driving habits that can result in a premium discount. For example, if you and your passengers always wear a seat belt, Geico offers a discount of up to "15% off the medical payments or personal injury protection portion of your premium."

Vehicle equipment discounts

4. Air bag discount. Most new cars come with supplemental restraint systems. If your car has air bags, make sure you get the discount from your insurance carrier. Allstate, for example, offers discounts of up to 30% if your vehicle is equipped with passive restraints (including motorized seat belts).

5. Anti-lock brakes discount. Not only can anti-lock brakes help you avoid an accident, they can shave about 5% to 10% off the collision portion of your insurance.

6. Anti-theft system discount. An alarm system can knock another 10% off your premiums. Factory-installed systems get you this discount. Don't count on the same savings if you try to install a system on your own.

Payment discounts

7. Pay-in-full discount. This is one that many people miss. Your premiums go down if you pay six months at a time. If you want to pay monthly, the cost will go up, sometimes significantly. The key here is to save well in advance of your premium due date so that you have the money in hand when your insurance bill is due. (Post continues below.)

8. Automatic payment discount. This one was new to me. Some insurance companies will offer a discount if you set up automatic payments from your bank account. Related to this, Progressive offers a $50 savings immediately if you sign up for insurance online.

Driver education discounts

9. Good student discount. If your teenager has good grades, you'll qualify for a student discount. With Nationwide, our kids had to maintain a 3.0 grade-point average, and the savings were significant.

10. Resident student discount. This is one we are taking advantage of now. If your child heads off to a college more than 100 miles from home without a car, you can qualify for a substantial discount. The actual distance the school must be from home varies, so be sure to check with your insurance carrier.

11. Defensive driver discount. If you take a defensive driver course, that can save you as much as 10% off your insurance.

Customer loyalty discounts

12. Multiple car discount. Presumably if you have multiple vehicles, they are insured with the same company. But if not, consider that most carriers offer discounts when you insure more than one vehicle.

13. Long-term customer discount. This is one we take advantage of with Nationwide. I've been with the same insurance company for nearly 30 years. Not only do we get a substantial discount as a result of our loyalty, but we also qualify for a special status that basically means they will never deny us insurance.

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14. Multiple policies discount. If you get all your insurance (auto, life, home) from the same carrier, you'll qualify for additional discounts. This is another one we take advantage of, and it makes paying our premiums easier because we deal with just one company.

Bonus discount

15. Good credit score discount. Although this one isn't technically a discount, it's one that many people miss. Insurance companies use credit scores and history to set premiums. The higher your score, the less you'll pay. So make sure to keep your credit score in good health.

More on The Dough Roller and MSN Money:

• 25 factors that affect auto insurance premiums
• Ways to reduce your car insurance bill
• The ins and outs of car insurance deductibles
• The most and least expensive cars to insure
• Special plates for teen drivers?
• 6 secrets of car insurers