When it comes to fraud in the United States, it’s the coasts with the most. Five of the top 10 riskiest shipping ZIP codes are in or near Miami. California ZIP codes take three of the top 10 spots, according to a new study.

E-retailers can benefit from knowing where fraud occurs because that knowledge adds a layer of verification when assessing the risk of whether an online order is legitimate, according to Experian, which analyzed data on fraud attack rates for shipping and billing locations. Shipping states are associated with criminals committing fraud (the address where purchased goods are sent), and billing states are associated with fraud victims (the address of the purchaser), Experian says.

Seven states—Florida, Oregon, Delaware, California, New York, Georgia and Nevada—plus Puerto Rico, rank higher than average on the attack rate threshold for shipping and billing fraud. However, the majority of U.S. states are at or below the average attack rate threshold for both shipping and billing fraud, which  indicates that attackers target consumers equally in higher-risk states and use addresses from higher- and lower-risk states to ship and receive fraudulent goods, the report says. For its study, Experian analyzed millions of e-commerce transactions to calculate attack rates using “bad transactions” in relation to the total number of transactions for 2015.

Many higher-risk states are near a large port-of-entry city, including Miami; Portland, Ore.; and Washington, D.C., all of which are among the riskiest cities for shipping and billing fraud. Such proximity lets criminals move stolen goods more effectively, Experian says.

Miami is a major hub for international commerce with its proximity to the Caribbean and South America, plus the airport and port that handle international trade, says Adam Fingersh, Experian general manager and senior vice president of Fraud & Identity Solutions. “There are numerous freight forwarders in the area because of this and as a result, Miami accounted for the most (risky) ZIP codes of any city. The same characteristics can be said of Florida, too, with many international airports and other port cities within the state,” he says.

“Fraud follows the path of least resistance. With more shipping and billing options available to create a better customer experience, criminals attempt to exploit any added convenience,” Fingersh says. “E-commerce fraud is not confined to larger cities since fraudsters can ship items anywhere.”

A case in point: Eudora, Kan. (population 6,211, according to 2013 census data), has the overall riskiest ZIP code for shipping fraud, but no other Kansas cities or towns appear in the top 100, Experian says. Eudora did not have any of the riskiest ZIP codes all year until the week of Black Friday and Cyber Monday (the Friday and Monday after Thanksgiving), which saw a significant increase in attack rates, Experian says, which could not pinpoint the reason.

The top 10 riskiest shipping ZIP codes are:

• 91733, South El Monte, Calif.
• 33195, Miami
• 33192, Miami
• 33172, Miami
• 33166, Miami
• 90603, Whittier, Calif.
• 66025, Eudora, Kan.
• 94536, Fremont, Calif.
• 33150, Miami
• 37385, Tellico Plains, Tenn.

The top 10 riskiest billing ZIP codes are:

• 66025, Eudora, Kan.
• 33178, Miami
• 02210, Boston
• 90603, Whittier, Calif.
• 30303, Atlanta
• 33172, Miami
• 90001, Los Angeles
• 94536, Fremont, Calif.
• 37385, Tellico Plains, Tenn.
• 33122, Miami