The most obvious thing you can do to lower your car insurance costs is to follow the rules of the road and build a good driving history. If you are a safe driver, your rates will go down over time, but one serious mistake could set you all the way back to square one. Your credit score is going to be important to insurance companies because that is how they measure your financial stability, one of the factors assessed when your premiums are set.
Other factors that affect your auto insurance premiums include where your car is parked at night, such as in a bad neighborhood, or whether your car is adequately sheltered, such as in a private garage. If your job is considered an increased risk or you drive long distances regularly, you can expect higher premiums, but government employees and medical workers may qualify for discounts due to their professions.
Changing your deductible increases the amount of money you have to pay out of pocket before your insurance kicks in, but it also reduces the monthly premiums. As long as you are financially able to pay for some of the damage yourself, you can save money over the long term. You might also consider getting a lower risk automobile, such as an older model that doesn't really need the same level of coverage as a newer car. If changing cars is not an option, install a security alarm to reduce the risk.
Look at your policy. Do you have more coverage than you need? If you have an older car, you probably don't need comprehensive coverage, just the minimums allowed by law. Similarly, if the car is in top condition, paying more on your insurance for towing insurance may not be necessary.
If you are under 25 and live in your parent's home, you could get added to their insurance. This keeps the premiums down by avoiding the insurance risk of drivers under 25. You can also lower your rates by taking a voluntary driver safety course. Just notify the insurance company after you've completed the course and ask them for any discount which is available.