Insurance companies can get your mileage without your knowledge. Here's how it may cost you

SAN FRANCISCO (KGO) -- This story is about Nathaniel Epting and his car insurance. It started with a letter Epting opened.

"I'm like great," he tells me, "I have to pay my car insurance. I looked at it, and I was like, 'It's up about $400.'"

Almost a third more than what he had been paying. So he asked his CSAA auto insurance agent: why?

"He realized that it was my mileage, and my mileage was reported as being significantly higher than the year before, and I was like, that's interesting, because I haven't really reported any mileage recently, or anything like that," says Epting.

If he didn't report driving more, who did?

Let's look at his insurance paperwork. Last year's "estimate annual miles driven" was 3,000. This year's paperwork shows that 3,000 miles, but a new category is added: "future annual miles" -- and the number is more than four times higher at 12,880 miles.

Epting shares his agent's response.

"So he's like, 'Yeah, well, we're starting to take it, from like, if you go get an oil change and stuff like that, that will get reported, and we'll be able to use that information,'" he says.

Turns out under certain circumstances, insurers have the legal right to figure out -- on their own -- how much a policyholder will drive. I wanted to ask CSAA Insurance how it determined Epting's mileage but it wouldn't talk with me about it.

The Insurance Information Institute's Janet Ruiz says insurance companies have any number of ways to determine how much you drive, including information noted when your car is in the shop. "Repair shops also record mileage when you take your car in for oil changes, or getting a repair after an accident," she says.

Consumer Watchdog's Carmen Balber says policy holders must be asked about their mileage, but not that often.

"They only technically have to ask every three years. So in the meantime, they're allowed to use other sources for that information, and that can be things like DMV records of your smog check, which records your mileage," Balber says.

Consumer Watchdog says the information must be from a government source, but not necessarily directly.

Which brings us back to Epting who says he had been driving a lot more, still he doesn't like how this whole thing went down.

"I can't help but feel as a customer, and a consumer who needs car insurance, that this is just an easy way to squeeze money out of people after an era where people aren't driving as much," he says.

Now here is what you need to know. You have the right to challenge any mileage determined by the company and it is easy to do. Have your odometer reading and what you believe you'll be driving in the upcoming year. Then call your agent or insurance company and make your case. I just did it myself and saved plenty.

Take a look at more stories and videos by Michael Finney and 7 On Your Side.

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