This is a list of some of the ways regions are defined in the United States. Many regions are defined in law or regulations by the federal government; others by shared culture and history, and others by economic factors.
Interstate regions
Census Bureau–designated regions and divisions
Since 1950, the United States Census Bureau defines four statistical regions, with nine divisions.[1][2] The Census Bureau region definition is "widely used ... for data collection and analysis",[3] and is the most commonly used classification system.[4][5][6][7]
Puerto Rico and other US territories are not part of any census region or census division.[9]
Federal Reserve Banks
The Federal Reserve Act of 1913 divided the country into twelve districts with a central Federal Reserve Bank in each district. These twelve Federal Reserve Banks together form a major part of the Federal Reserve System, the central banking system of the United States. Missouri is the only U.S. state to have two Federal Reserve locations within its borders, but several other states are also divided between more than one district.
The Federal Circuit is not a regional circuit. Its jurisdiction is nationwide but based on the subject matter.
Agency administrative regions
In 1969, the Office of Management and Budget published a list of ten "Standard Federal Regions",[11] to which federal agencies could be restructured as a means of standardizing government administration nationwide. Despite a finding in 1977 that this restructuring did not reduce administrative costs as initially expected,[12]and the complete rescinding of the standard region system in 1995,[13]several agencies continue to follow the system, including the Environmental Protection Agency[14] and the Department of Housing and Urban Development.[15]