Census-designated places

A census-designated place (CDP) is a concentration of population defined by the United States Census Bureau for statistical purposes only. CDPs have been used in each decennial census since 1980 as the counterparts of incorporated places, such as self-governing cities, towns, and villages for the purposes of gathering and correlating statistical data. CDPs are populated areas that generally include one officially designated but currently unincorporated small community, for which the CDP is named, plus surrounding inhabited countryside of varying dimensions and, occasionally, other, smaller unincorporated communities as well. CDPs include small rural communities, colonias located along the U.S. border with Mexico, and unincorporated resort and retirement communities and their environs.

The boundaries of a CDP have no legal status. Thus, they may not always correspond with the local understanding of the area or community with the same name. However, criteria established for the 2010 Census require that a CDP name "be one that is recognized and used in daily communication by the residents of the community" (not "a name developed solely for planning or other purposes") and recommend that a CDP's boundaries be mapped based on the geographic extent associated with inhabitants' regular use of the named place.

The Census Bureau states that census-designated places are not considered incorporated places and that it includes only census-designated places in its city population list for Hawaii because that state has no incorporated cities. In addition, census city lists from 2007 include Arlington County, Virginia's CDP in the list with the incorporated places.

The Census Bureau reported data for some unincorporated places as early as the 1850 Census, though usage continued to develop through the 1890 Census, in which, for the first time, the Census mixed unincorporated places with incorporated places in its products with "town" or "village" as its label. This made it confusing to determine which of the "towns" were or were not incorporated.

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