Homeowners with poor credit pay 91 percent more for homeowners’ insurance than people with excellent credit, according to a study by an online insurance shopping service.

The report by insuranceQuotes.com also found that homeowners with median credit pay 29 percent more than those with excellent credit.

People with poor credit pay at least twice as much as people with excellent credit in 37 states and Washington, D.C. West Virginia’s 208 percent increase is the highest in the nation, followed by Virginia (186 percent), Ohio (185 percent) and Washington, D.C. (182 percent).

The greatest differences between excellent and median credit were observed in Montana (65 percent), Washington, D.C. (60 percent) and Arizona (55 percent).

“This is another example of why credit is such an important part of your financial life,” said Laura Adams, senior analyst, insuranceQuotes.com. “Maintaining a good credit history suggests that you’re a less risky customer and can lead to several hundred dollars in annual homeowners’ insurance savings.”

Three states prohibit insurers from using credit to calculate homeowner’s insurance premiums: California, Massachusetts and Maryland.

In Florida, while insurance companies are technically allowed to consider homeowners’ credit scores, insuranceQuotes.com said it found that credit does not typically affect premiums. Florida’s hurricane-prone location means that homeowners pay the highest homeowners’ insurance rates in the nation ($1,933 per year, which is almost double the national average of $978, according to the National Association of Insurance Commissioners). Credit appears to be a lesser concern in Florida’s homeowners’ insurance market.

According to the NAIC, about 85 percent of home insurers use credit-based insurance scores in states where it’s allowed.

According to insuranceQuotes.com, the following five states showed the greatest average premium increase after an excellent credit is downgraded to fair.

1. Montana — 65 percent increase
2. Washington, D.C. — 60 percent
3. Arizona — 55 percent
4. West Virginia — 53 percent
5. Virginia — 52 percent

Excluding Maryland, Massachusetts and California, the following five states showed the smallest percentage increase after an excellent credit is downgraded to fair.

• Florida — 0 percent increase
• Hawaii — 6 percent
• New York — 11 percent
• North Carolina — 13 percent
• Wyoming — 18 percent

For the research, insuranceQuotes.com said it commissioned Quadrant Information Services to examine how credit affects homeowners’ insurance premiums. Quadrant calculated rates using data from six major carriers representing approximately 60 percent of market share in all 50 states and Washington, D.C. As the report notes, insurance credit scores, unlike traditional credit scores used by lenders and credit card companies,  are not disclosed to consumers. Also, individual insurers vary in how much weight they give credit scores in their pricing and underwriting.

More information, including the findings for all 50 states and Washington, D.C., is available here.

How to improve your credit-based insurance score

There are ways you can improve your credit-based insurance score the same way you can boost your regular credit score. A few tips include:

• Pay all of your credit card debts and installment loans on time.
• Don't open any new credit accounts unless it's an absolute necessity.
• Keep credit card balances as low as possible -- ideally about 25 percent of your available credit limit.
• Shop around. Barry says, spokesman for nonprofit Insurance Information Institute, "If you find that your credit score is rising but your premium doesn't fall, that means it's time to shop around for another home insurer, because you can probably find a more affordable policy."