What are America's wealthiest zip codes? Experian, an information services group, has created an extensive map highlighting the wealthiest zip codes based on individual income tax returns around the country. (Click here for a higher-res version that you can zoom in on.)

For each state, the maps lists the top three wealthiest zip codes based on adjusted income figures from the IRS. The number at the top right indicates how many tax returns were filed in the zip code, while the number below it is the average income reported by residents. The zip codes marked in gray have the highest average income in the state, while those marked in red have the highest average income in the region.

Some of these zip codes are very small, with only a few dozen filers. As Jed Kolko, the former chief economist at Trulia, points out, many are actually non-resident locations like company headquarters or government buildings.

In the Washington, D.C. area, for example, 20510, which includes the Senate office buildings, ranks as the wealthiest zip code in the District, with an average income of $191,818. In Maryland, the wealthiest zip code is 21056, Gibson Island, with an average income of $450,012. In Virginia it's Roanoke (24005), with an average income of $394,400. Experian puts Washington, D.C. in the South-Atlantic region. The wealthiest zip code in the region is in Florida -- Miami Beach (33109) with a stunning $2,180,105 in average income. 

Here are the same results for the North East - Middle Atlantic and the North East - New England. It probably won't surprise you that New York City has the wealthiest zip code in the Middle Atlantic (10104), with an average income of $2,976,929. In New England, Greenwich, Conn. (06831) ranks first, with $414,686.

Here are those same results for the rest of the North, the South and Rocky mountains, and the West coast:

The top five zip codes in America with the highest average income probably won’t surprise you: three of the five are in New York City, while one is in Miami Beach.

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