CDPs are defined as populated areas that are not organized into incorporated communities.
The names and boundaries of CDPs are defined by the US Census Bureau with the cooperation of state and local officials but have no legal standing.
[1] As such, they may be annexed in part or in whole by adjoining cities and towns, become incorporated as part of a new city or town, or be redefined in a subsequent census.
While many CDPs are small, rural communities with insufficient population to support incorporation, this is not always the case.
Included in this list are large, urbanized communities such as Sun City, a retirement community of 37,499 residents, or San Tan Valley, a large suburb of the Phoenix Metropolitan Area whose 81,321 inhabitants would make it the largest city or town in Pinal County were it to incorporate.