Source: Mark Turnaukas, Flickr.

The average American driver will file a claim with his or her car insurer about every 18 years, on average, or about three or four times in a lifetime. You probably know that it's not going to be good for your car-insurance premiums if you are involved in an accident. But odds are, you have no idea just how much a single accident -- or a stolen car -- can affect the rates you're charged.

The folks at insurancequotes.com recently released a report on the topic, with some eye-opening findings: Insured drivers who file a claim valued at $2,000 are likely to be socked with an increase in the cost of their insurance of 41% on average. For someone paying the national average cost of car insurance of roughly $1,300 per year (for a 40-year-old man with a good driving record), that would be an increase of about $533. Yowza, right?

The rate hikes (often called "surcharges") happen because all of a sudden, you're deemed a higher-risk driver.

It gets worse
Some unlucky souls might be involved in two accidents in a year. If that happens to you and you file two claims with your insurer, you can expect to be hit with an increase of, on average... 93%! That's right -- your rate might nearly double.

The whole issue is more complicated than it looks because insurers each look at different factors -- such as who was at fault in an accident, your driving history, how serious an accident was, and sometimes your credit score, age, gender, and occupation, as well -- and then weigh them differently. Thus, your rates will increase by a different amount depending on your insurer. They will also vary depending on your state -- and sometimes even your zip code!

A second claim makes things worse. Source: Jay-P, Flickr.

The 41% and 93% averages above are just that: averages. Some states and some insurers will be harsher than others. Massachusetts is known to levy big rate increases, for example, while Maryland is relatively lenient.

Know that the type of claim can matter, too. The most costly claim is one for bodily injury, and a single $2,000 one can get your rate hiked by 86% in California and 27% in Oklahoma, on average, per insurancequotes.com.

It gets better
Fortunately, as financially painful as a significantly hiked rate can be, it won't last forever. These increases tend to remain in effect for up to three or so years, before fading away. Your rates will likely fall with each year of a clean driving record, returning to their original level.

Meanwhile, in many states, insurers are prohibited by law from raising your rates if you're not at fault in the accident -- or if the value of your claim is below a certain level. (Clearly, it's worth investigating the rules governing rate hikes in the state where you live!)

What to do
There are ways you can reduce the financial damage you might face from a post-claim rate hike, such as by being extra careful when driving, leaving ample braking room between your car and the one in front of you, not texting while driving, and so on. You can never eliminate the chance of an accident, but you can certainly reduce it.

If you do experience a rate hike, you might be able to appeal it, or get it reduced, so have a discussion with your insurer -- especially if you've been a loyal customer with a good record.

The greater the damage, the more sense it makes to file a claim. Source: Jason Schultz, Flickr.

You can also benefit by shopping around when buying car insurance. Some insurers, for example, offer a one-accident forgiveness feature, promising to not raise your rate when you file your first claim. You can also shop around after an accident that spiked your rates, as different insurers will factor that incident differently in their calculations, offering you different rates. Consider having a high deductible on your policy, too, which can significantly lower your rates.

It's often smart to suck it up and just pay for needed repairs, if you can, without filing a claim. It depends on the scope of the damage and the cost, of course, but not filing a claim, especially a small one, is often an option worth considering.