Decatur County area

Decatur County, Tennessee covers 344.9 square miles: 333.9 square miles of land and 11 square miles of water. Its county seat is Decaturville. An estimated 11,820 people lived there in 2025.

Official Census measurements · GEOID 470392026 Gazetteer · retrieved September 27, 2026
Land area333.9 mi²
Water area11 mi²
Population (2025)11,820
People per mi²35

County outline

Generalized outline of Decatur County, Tennessee
2025 Census cartographic boundary, fitted to this frame. County maps are not at a common scale. The 2026 area measurements below come from the separate Gazetteer release. Map source and limitations.

Where Decatur County is located

Decatur County highlighted on a map of all U.S. county equivalents. About the maps

Area breakdown

Land accounts for 96.8% of Decatur County’s measured area and water for 3.2%. Its combined area converts to 893.2 square kilometers or approximately 220,725 acres.

Green: land · blue: water

MeasurementSquare milesSquare kilometersAcres
Land333.879864.743213,682.6
Water11.00428.57,042.6
Total344.883893.243220,725.1

How Decatur County compares

By original Census land area, Decatur County ranks #66 of 95 in Tennessee and #2730 of 3,222 nationally. National rankings include the 50 states, District of Columbia, and Puerto Rico.

Its land area is 0.766 times the Tennessee county-equivalent median of 436.1 square miles. It accounts for 0.8% of the combined county land area in the state.

See the complete Tennessee ranking · What counts as a county equivalent?

Population and density of Decatur County

The Census Bureau estimates that 11,820 people lived in Decatur County on July 1, 2025. That ranks #2,364 of 3,222 county equivalents nationally and #87 of 95 in Tennessee. Since the April 1, 2020 estimates base of 11,434, the population has grown by 386 (+3.4%), compared with +5.8% for Tennessee as a whole.

With 333.9 square miles of land, that is 35 people per square mile (14 per km²), placing Decatur County #1,865 nationally for density and #87 in Tennessee. The median county equivalent has 47 people per square mile; the Tennessee median is 76. Put another way, there are about 18 acres of land per resident.

Estimated population, 2020–2025 · line scaled to this county’s own range
July 1202020212022202320242025
Estimate11,42911,39211,52711,68511,73811,820
Change—−37+135+158+53+82

U.S. Census Bureau, Vintage 2025 population estimates. Estimates are revised each year and are not decennial census counts. Density divides the whole population by the whole county’s land area, so it describes an average, not how settlement is distributed within the county. Population sources and methods.

Cities and towns in Decatur County

3 incorporated places lie at least partly in Decatur County. Together they are home to 3,306 people (28%); the other 8,514 (72%) live outside any incorporated place, in unincorporated communities and rural areas.

The largest is Parsons city, with 2,162 residents in the county. The county seat, Decaturville town, has 813 residents.

Incorporated placePopulation 2025Since 2020Land mi²
Parsons city2,162+3.3%4.032
Decaturville townCounty seat813+1%1.652
Scotts Hill townAlso in 1 other county331+7.5%3.666

Population: U.S. Census Bureau Vintage 2025 subcounty estimates, counting only the part of each place inside Decatur County. Land: 2026 Census Gazetteer, for the whole place even where it extends into other counties. How communities are listed.

Metropolitan area

Decatur County is not part of any metropolitan or micropolitan statistical area in the Office of Management and Budget’s July 2023 delineation; 1,306 other county equivalents are also outside one. These areas are built around an urban core of at least 10,000 people plus the counties tied to it by commuting, so counties outside them are generally rural.

ZIP codes

9 ZIP Code Tabulation Areas have land in Decatur County; 5 of them have most of their land inside the county, and the others mainly cover neighboring areas.

383113832838329383413836338371383743838038388

ZIP Code Tabulation Areas are the Census Bureau’s approximations of USPS ZIP Code service areas, from the 2020 Census relationship files. Lighter codes have less than half of their land in this county. Post-office-box and single-address ZIP Codes have no tabulation area.

Counties bordering Decatur County

Decatur County shares a land border with 6 county equivalents. Each of them has more land than Decatur County. The largest neighbor is Wayne County (734.1 mi²) and the smallest is Benton County (394.3 mi²). Together with its neighbors, Decatur County forms a block of 3,572.2 mi² of land, of which it holds 9.3%.

Map of Decatur County and the 6 county equivalents that border it Perry County, Tennessee: 414.8 mi² landHenderson County, Tennessee: 520 mi² landHardin County, Tennessee: 577.5 mi² landBenton County, Tennessee: 394.3 mi² landWayne County, Tennessee: 734.1 mi² landCarroll County, Tennessee: 597.7 mi² land
Decatur County (dark) and its bordering county equivalents. Select a neighbor to open its profile. Drawn from the 2025 Census cartographic boundaries in an equal-area projection. How borders are determined.
Bordering county equivalentLand mi²Size vs. DecaturCompare
Wayne County734.12.2× largerCompare
Carroll County597.71.8× largerCompare
Hardin County577.51.7× largerCompare
Henderson County5201.6× largerCompare
Perry County414.81.2× largerCompare
Benton County394.31.2× largerCompare

How big is Decatur County compared with U.S. states?

Decatur County has less land than any of the 50 states. Rhode Island, the smallest state by land area, has 1,033.9 mi², about 3.1 times as much. Tennessee’s county land could hold about 123 areas the size of Decatur County.

Land area: Decatur County and the closest-sized states
Decatur County333.9 mi²
Rhode Island1,033.9 mi²

Another way to picture it: the same land area would fill a square about 18.3 miles (29.4 km) on each side. Real county shapes are rarely square, so this is a scale reference rather than a width or driving distance.

State figures are the sums of each state’s county-equivalent land measurements in the same Census release, so states and counties are compared on the same basis. Published state totals can differ slightly because of rounding. Compare all states · Counties bigger than entire states.

What stands out about Decatur County?

Decatur County has more land than 492 of the other 3,221 county equivalents in the dataset.

Land area compared with the typical county equivalent
Decatur County333.9 mi²
Tennessee median436.1 mi²
National median604.5 mi²

A median is the middle county-equivalent measurement, not the average of the largest and smallest. All three bars use the same linear scale. Very small areas may appear as a thin sliver; the labels retain their values.

Does including water change its rank?

Using land plus water places Decatur County at #2,746 nationally by total area, 16 places farther from the top than its land rank. Other county equivalents gain more area when their water measurements are included.

Its water share is 3.2%, compared with a national county-equivalent median of 1.2% — 2 percentage points higher. This describes the statistical geography’s land/water mix, not flood exposure or developable land.

Closest positions in the national land ranking

These entries sit immediately beside Decatur County in the national ranking. They can be in different states and are not necessarily geographic neighbors.

Land rankCounty equivalentLand mi²Comparison
#2729Appomattox County, Virginia334.2Compare
#2730Decatur County, Tennessee333.9This county
#2731Orange County, Texas333.8Compare

Calculated from the same Census release as the area table. Total-area order uses original ALAND + AWATER; water shares and chart labels use published square miles. Calculation details.

Representative coordinates

The Census internal point is 35.603136, -88.110292. It represents a location inside the geography; it is not necessarily the centroid or the address of a courthouse.

Source and precision

U.S. Census Bureau, 2026 Gazetteer Files, Counties. Original ALAND: 864,741,761 m²; AWATER: 28,500,999 m². Rankings use ALAND; exact ties use ascending GEOID. Tables preserve Census-published square miles to three decimals, with conversions based on those values.

Download the official county source ZIP ↗ · Methodology

Common questions

How big is Decatur County?

Decatur County, Tennessee has 333.9 square miles (864.7 km²) of land and 11 square miles of water, for a total area of 344.9 square miles. It ranks #2730 of 3,222 U.S. county equivalents by land area.

Is Decatur County the largest county in Tennessee?

No. Decatur County ranks #66 of 95 in Tennessee by land area. The largest is Shelby County, with 752.8 square miles of land.

What counties border Decatur County?

Decatur County shares a land border with Perry County, Henderson County, Hardin County, Benton County, Wayne County, and Carroll County.

What is the population of Decatur County?

The Census Bureau estimates Decatur County had 11,820 residents on July 1, 2025, ranking #2,364 of 3,222 county equivalents. That is 35 people per square mile of land.

What is the county seat of Decatur County?

The county seat of Decatur County is Decaturville.

What cities and towns are in Decatur County?

Decatur County has 3 incorporated places. The most populous are Parsons city, Decaturville town, and Scotts Hill town; 8,514 residents live outside any incorporated place.

Is Decatur County part of a metropolitan area?

No. Decatur County is outside every metropolitan and micropolitan statistical area in the July 2023 OMB delineation.

How many ZIP codes are in Decatur County?

9 ZIP Code Tabulation Areas have land in Decatur County, and 5 of them have most of their land inside the county. Census ZIP Code Tabulation Areas approximate USPS ZIP Code areas.

How does Decatur County compare with U.S. states?

It has less land than every state. Rhode Island, the smallest, has 3.1 times as much land.

How many acres of land are in Decatur County?

The land measurement converts to approximately 213,683 acres. Including water, total area is approximately 220,725 acres. One square mile equals 640 acres.

Why might another source show a different area?

Check whether it reports land or total area, its Census vintage, and its rounding. Our guide explains how to reconcile county area figures.

Can this establish a property boundary?

No. Statistical measurements and generalized maps do not establish property lines. Consult the relevant local surveying or land-records authority.

Cite this county

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