List of highest-income counties in the United States

There are 3,144 counties and county-equivalents in the United States. The source of the data is the U.S. Census Bureau and the data is current as of the indicated year. Independent cities are considered county-equivalent by the Census Bureau.

Before the American Civil War, the wealthiest counties were primarily located in Louisiana and Mississippi.

The Loudoun County, Virginia suburb of Washington, D.C. is the highest-income county by median household income. Another Washington suburb, Arlington County, Virginia, ranks as the highest-income county by median family income.

Many of the top counties in the following lists are found in the Northeast Megalopolis, particularly in the Washington metropolitan area and the New York metropolitan area.

Presented below are the 25 wealthiest counties (with populations of 65,000 or greater) in the United States by median household income according to the 2012 American Community Survey prepared by the US Census Bureau. Six of the counties are located in the state of Maryland, five are in Virginia, four in New Jersey, three in New York, two in California, and one each in: Colorado, Georgia, Michigan, Tennessee, and Texas.

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