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Cutting your auto insurance bill might be as simple as asking if you qualify for a better deal.

Just 16 percent of consumers have asked their auto insurer for common breaks like low-mileage rates or good-student discounts, according to a new InsuranceQuotes.com survey of 1,000 adults.

That's a mistake that can leave big money on the table. In California, for example, where the average insurance premium is $750, someone who gets a low mileage discount for driving 5,000 miles per year instead of the average 15,000 could save as much as 25 percent, according to InsuranceQuotes.com data.

A married 20-year-old could pay up to 21 percent less than a single person of the same age, for example, but the survey found that only 13 percent of the adults had alerted their insurer after they tied the knot.

The fix is simple: "Ask what discounts are available, and ask regularly," said Amy Danise, an insurance expert with NerdWallet.com. Discounts vary by insurance carrier and state, but an agent should be able to walk you through which are available. Alert your agent when you have a life change—be it a move, a new job or a family shift—that could benefit your rate. And keep the potential for discounts in mind when shopping competitors for a new rate, Adams said. Initial quotes may not account for discount-qualifying details like whether you've taken a defensive driving class or if you're an A+ student.

Tips on how to buy a car

May 12, 201501:53

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