After a few years of holding steady, auto insurance premiums are rising. In most states, they’re expected to increase over the next few years even more due to higher repair costs, inflated values of used cars, increasing claims, and near-record numbers of injuries and fatalities from car accidents.

Most drivers stick with the same company year after year, and that’s often a costly mistake. They don’t shop for lower rates because they believe most companies charge about the same prices or conclude that the steep discounts they get (for their loyalty, or lack of speeding tickets or accidents) mean they won’t find better pricing elsewhere. But they’re wrong: Insurance companies charge vastly different rates for the same families and policies, and although you might be getting a price break from your current company, its competitors will also probably offer you deals to gain your business.

Our researchers collected rates for seven typical policyholders from large insurers operating in the Chicago area. We found that by spending a few hours to compare rates, most drivers will save hundreds of dollars—more than $2,500 a year in some cases—by switching to lower-cost companies.

If you find a better rate, don’t bother waiting until your current policy term expires to switch. After you sign with a different company, you can cancel your old policy and your old insurer is required to refund any unused share of prepaid premiums. And you don’t have to forsake good service for a better rate: Our ratings reveal low-priced yet highly rated companies.

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It’s unlikely that the rates we report will apply exactly to you and your family. You don’t live at the addresses we used, drive different cars, probably have a different driving record and loss history, and differ in other important ways. And because insurers use increasingly complex formulas to set rates, the companies that offered the lowest rates for our illustrative policyholders might not offer you good rates, too. Unfortunately, you’ll have to collect proposals from several insurers to determine which companies will give you the best rates.

Keep in mind also that the rates we collected apply to policies that would be new business for the insurers; companies often charge existing customers substantially different rates than what they offer to new applicants.

You can shop by using companies’ websites or by calling the companies directly. Some companies sell only through agents.

When contacting agents, you may have to push for reliable information. We often find some agents quote wildly inaccurate rates, while others persistently push more coverage than requested. Before shopping, make a list of the coverages you plan to purchase. Our article "How Much Auto Insurance Coverage Do You Need?" provides advice on which coverages to buy, how much to buy, and what to skip.

Don’t bother using rate-comparison websites such as EverQuote.com, Gabi.com, Insurify.com, QuoteWizard.com, TheZebra.com, and many others. We tried out dozens of these sites and found it an utter waste of time. We rarely were provided with any meaningful price information; instead, our contact info was served up to other companies and agents as sales leads, unleashing a barrage of calls, texts, and emails that still didn’t include the pricing info we sought.