Men and women pay different car insurance rates in many US states.

In 2016, women’s car insurance rates were higher than men’s in 12 states, according to an analysis by car-insurance comparison site The Zebra.

By 2018, women paid more for car insurance in 25 states, and the cost disparity is growing.

California recently joined five other states in banning gender-based car insurance pricing.

It turns out many insurance companies care whether or not you drive like a girl.

In 44 US states, insurance companies can use gender to determine a driver’s car insurance rate. There’s a lot of opposing data about whether men or women are riskier on the road, but insurers often use their own research to determine car-insurance premiums, which has led to widespread disparities.

Car insurance rates are also based on age, credit, car make and model, driving record, and location. The average price of car insurance premiums nationwide is $US125 a month.

But a new analysis by car-insurance comparison site The Zebra reveals that in 2018 women paid more for car insurance on average in 25 states, while men paid more in 20 states and Washington DC.

Earlier this year, California banned gender-based car insurance rates, joining five states – Hawaii, Massachusetts, Montana, North Carolina, and Pennsylvania – that already prohibit the practice.

Here’s who paid higher car insurance rates in every state in 2018:

Shayanne Gal/Business Insider

Though the total number of states where women pay more versus where men pay more is nearly the same, it wasn’t that way just two years ago.

According to The Zebra, women paid more on average in just 12 states in 2016. The Zebra concluded that women’s rates are increasing compared to men’s in many places and the cost differences are also becoming more stark. In Nevada, for example, women paid just $US14 more on average than men in 2016 compared to $US121 more in 2018.

Here’s who paid higher car insurance rates in every state in 2016 vs. 2018:

Shayanne Gal/Business Insider

The Zebra’s analysis used the following base profile to compare insurance rates: A 30-year-old single male or female driving a 4-year-old Honda Accord EX with a good driving history; coverage limits of $US50,000 bodily injury liability per person, $US100,000 bodily injury liability per accident, and $US50,000 property damage liability per accident with a $US500 deductible for comprehensive and collision.

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