It's not quite Big Brother, but many American motorists are allowing their insurance companies to keep a close eye on what they do while behind the wheel. And millions more may soon follow.
According to a new survey, more than half of all American drivers are willing to give insurance companies the authorization to review their driving habits in return for lower insurance rates.
The research, conducted by the Deloitte Center for Financial Services, found that 53 percent of respondents said they would allow their driving to be tracked via a mobile device in exchange for premium discounts based on their performance.
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Millennial drivers were the most open to data tracking, with nearly two-thirds of respondents between ages 21 and 29 willing to give up their information. That compares to only 44 percent for those 60 or older.
The survey found about half of the respondents thought they'd be entitled to discounts between 11 and 20 percent for allowing the companies to monitor their behavior.
More than a million drivers across the country are already taking part in pay-as-you-drive or usage-based insurance coverage from large providers, such as Allstate, Progressive and State Farm, according to the most recent estimates.
Allstate, one of the nation's largest insurance companies, allows drivers in 30 states to save money through its Drivewise program by proving they are safe drivers. By connecting a device to the vehicle, the policy tracks mileage, hard braking, speed and time of day when a vehicle is in use. Using the technology to gather the data, Allstate says it rewards drivers for being safe on the road.
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"We are committed to helping create a safer, more self-aware driver and, in doing so, we are able to pass along significant savings for safer driving," said Sarah Inciong, director of operations for Drivewise. "Having more customers participate offers us even more insight into the impact of various driving behaviors, which can help improve the product and our customer's driving habits."
Allstate says the average client receives rewards equal to 13 percent of their normal insurance bill. Progressive, which uses a Snapshot data tracker, says the technology has yielded motorists an average discount of $150 a year.
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Despite these savings, not everyone is comfortable with bringing an insurance company along for the ride.
A recent survey by the University of Michigan found the majority of Americans believe that having connected vehicles will make driving safer, but most are concerned about security and privacy.
—By CNBC Contributor Paul A. Eisenstein.