This is a list the 50 largest U.S. counties and county equivalents by gross domestic product in US$, representing the year at the top of the column, unless otherwise specified.
New York County is coterminous with the Borough of Manhattan, and is part of the City of New York, along with Kings County (Brooklyn), Queens County (Queens), Bronx County (The Bronx), and Richmond County (Staten Island). The figure shown here is for New York County/Manhattan, and does not include the other four boroughs' GDP.
Denver, Philadelphia, and San Francisco are consolidated city-counties.
The District of Columbia is a federal district, meaning it is not under any traditional city, county, or state government.
GDP divided by county population
List of the most populous counties in the United States