"If you're 20 and you're single, you're paying a much higher rate than you would if you were married at 20 years old. We're actually seeing a 21 percent difference, so a married 20-year-old is paying less than a single 20-year-old," Laura Adams, senior analyst at InsuranceQuotes.com, said in an interview.
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To be sure, there are a host of variables that go into calculating insurance rates, including driving history, geographic location, and the type of car being insured. Yet, InsuranceQuote's study sheds new light on what is effectively the reverse of the so-called "marriage penalty" paid by joint tax filers.
Generally, some insurers—but not all—see married male drivers as relatively more responsible than young single ones, which data suggests are more likely to be involved in drinking while driving incidents. The basis for this idea comes from a widely cited 2004 study by the National Institutes of Health, which showed that singles were twice as likely to get into motor accidents than married car operators. Insurers like State Farm also acknowledge that rates drop for men under 25 when they tie the knot.
Adams added that married consumers over age 30 also receive lower rates, yet those prices are not as favorable as what married people between the ages 20 and 25 receive. Car insurance rates for married over-30-year-olds only falls about 2 percent, the study found.
There are two other factors significantly affecting drivers' auto insurance quotes, the study said.
Your age group is one factor that could affect auto insurance rates, according to InsuranceQuotes. Insurance rates drop 41 percent from ages 20 to 25. Rates also drop another 18 percent from ages 25 to 60.
Nevertheless, rates for drivers of at least 75 years of age are 17 percent higher than that of 60-year-olds, the study found.
"Rates are quoted based on your group profile," Adams said. "If the insurance company knows that, in the past, 75-year-old drivers have submitted claims, they're going to factor that into their rate going forward."
InsuranceQuotes.com's study also found that gender influences policy prices.
Twenty-year-old men pay 22 percent more on auto insurance than 20-year-old women for the same coverage, with the gap narrowing only 3 percent at age 25. Interestingly, women between the ages of 30 and 55 are seen by insurers as a greater risk than men of the same age group—a reversal of the discount young female drivers sometimes receive.
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Variables such as driving history, and the make and model of the driver's car, play an important role in determining how much insurance will cost, according to InsuranceQuotes' Adams. "Whether you drive an Audi or a 2010 Toyota makes a big difference in the coverage amount," she said.
Also, consumers should be aware that their credit will play an important role in determining how much auto insurance will cost them, Adams added. "I can tell you is that it is growing in importance. More and more companies are really factoring it in."