FCSM Research & Policy Conference, Washington DC, October 26, 2022

Understanding Rural Definitions

John Cromartie

USDA, Economic Research Service

Disclaimer: The findings and conclusions in this presentation are those of the author and should not be construed to represent any official 

USDA determination or policy. This research was supported in part by the U.S. Department of Agriculture, Economic Research Service.
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The term ‘rural’ is applied to definitions based on 

different classification schemes

Research

• Rural areas are defined throughout this document using nonmetropolitan (nonmetro) 

counties.” (Rural America at a Glance, 2021 Edition)

• County population counts and estimates provide the basic accounting units for our 

analyses. We use the terms rural and nonmetropolitan interchangeably, as we do the 

terms urban and metropolitan. (Johnson and Lichter, Metropolitan Reclassification and 

the Urbanization of Rural America, Demography 57, 2020) 

Federal Programs

• For the purpose of water and waste disposal grants...the terms ‘rural’ and ‘rural area’ 

mean a city, town, or unincorporated area that has a population of no more than 

10,000 inhabitants. (USDA, Report On the Definition of Rural, 2013)

• Census tracts with RUCA codes 4 through 10 are considered rural for the purposes of 

Rural Health grants. (HHS Office of Rural Health Policy, List of Rural Counties And 

Designated Eligible Census Tracts in Metropolitan Counties)
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Drawing a precise line between urban and rural 

requires answering two questions: 

• At what population threshold do rural places become urban? 

• Where along the urban periphery do suburbs give way to rural 

territory? 

Answers vary tremendously, with dramatic differences in the resulting 

rural populations, in terms of overall size, geographic distribution, and 

socio-economic characteristics.
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“...the ability to...identify and remove 

barriers to equitable access to 

government programs is contingent on 

gathering the necessary data...”

“The term “equity” means the consistent 

and systematic fair, just, and impartial 

treatment of all individuals, including 

...Black, Latino, and...other persons of 

color; members of religious minorities; 

...LGBTQ+ persons; persons with 

disabilities; persons who live in rural 

areas; and persons otherwise adversely 

affected by persistent poverty or 

inequality.”

Rural Definitions and Measures Toolkit

John Cromartie and Michael Ratcliffe
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Four Sources of Rural Definitions and Their Four Key Features 
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Four Sources of Rural Definitions and Their Four Key Features 
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Census places

Advantages: 

• geographically detailed

• easy to understand, consisting of geography to which the 

public easily relates

• municipalities provide services relevant to rural development 

and are sometimes the targeted entity for federal funding

Disadvantages: 

• not statistically consistent in delineating high-density areas

• municipal incorporation and annexation laws differ by State

• actual population growth may or may not be reflected in 

boundary changes

• the CDP concept encompasses a variety of unincorporated 

communities
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Four Sources of Rural Definitions and Their Four Key Features 
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Census urban areas

Advantages: 

• geographic detail

• statistical consistency

o captures all densely-settled areas of a given town or city, regardless of 

municipal status

o the basic concept and the 2,500-person threshold has been in place since 

1910

Disadvantages: 

• not part of the Census Bureau’s annual population estimates program

• no annual economic data such as those available for counties

• does not follow municipal boundaries, so not a geography familiar to the public

• though the basic concept has not changed, criteria have been adjusted over the 

years, somewhat hampering analysis of urbanization trends over time
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Four Sources of Rural Definitions and Their Four Key Features 
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OMB’s Core-Based Statistical Areas (CBSAs)

Advantages

• composed of familiar geographic units; counties are typically active 

political jurisdictions, have stable borders, and usually have programmatic 

importance at the Federal and State level

• county population, employment, and income estimates available annually

• the Current Population Survey provides detailed demographic statistics 

annually for metro and nonmetro areas by State

• almost all research on rural conditions and trends refer to conditions in 

nonmetro areas

Disadvantages

• counties are often too large to precisely delineate labor market areas

• the underlying concept and 50,000-person threshold for metro areas have 

remained the same since they were first defined in 1950, but criteria have 

changed considerably with almost every decennial update, hampering the 

study of trends over time
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Four Sources of Rural Definitions and Their Four Key Features 
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ERS Rural-Urban Commuting Areas (RUCAs)

Advantages

• provides an alternative to OMB’s county-based system for situations where 

more detailed geographic delineation is needed

• allows for the identification of economic functional areas surrounding 

small towns, those between 2,500 and 10,000 population; counties are too 

large to adequately delineate these small labor market areas

Disadvantages

• census tracts and ZIP code areas are less familiar geographic entities, 

compared with counties or municipalities

• unstable boundaries; census tracts are routinely split, merged, or redefined 

in response to population change

• depends on measuring tract-to-tract commuting using data from the 

American Community Survey, which can include very small flows with high 

margins of error
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Census Bureau urban areas often diverge considerably from 

municipal boundaries
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Springfield, MO

St. Louis, MO

Little Rock, AR

Memphis, TN

Dallas-Fort Worth, TX

Oklahoma City, OK

Tulsa, OK

Wichita, KS

Kansas City, MO

County-based CBSAs extend far beyond their densely-settled cores
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Take-aways from the Rural Definitions and Measures 

Toolkit

• Delineating a clear line between rural and urban has always been problematic, 

but the complexity of today’s settlement system now makes futile any search 

for a one-size-fits-all solution. 

• A better strategy is to recognize that urban and rural are multi-dimensional 

concepts incorporating size, density, and distance perspectives. 

• The choice of a rural definition should be based first and foremost on the 

purpose of the enterprise. 

• Fortunately, the range of definitional options available today is quite broad.