Calhoun County area

Calhoun County, South Carolina covers 392.5 square miles: 381.1 square miles of land and 11.3 square miles of water. Its county seat is St. Matthews. An estimated 14,188 people lived there in 2025.

Official Census measurements · GEOID 450172026 Gazetteer · retrieved September 27, 2026
Land area381.1 mi²
Water area11.3 mi²
Population (2025)14,188
People per mi²37

County outline

Generalized outline of Calhoun County, South Carolina
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 Calhoun County is located

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

Area breakdown

Land accounts for 97.1% of Calhoun County’s measured area and water for 2.9%. Its combined area converts to 1,016.5 square kilometers or approximately 251,190 acres.

Green: land · blue: water

MeasurementSquare milesSquare kilometersAcres
Land381.146987.164243,933.4
Water11.33829.3657,256.3
Total392.4841,016.529251,189.8

How Calhoun County compares

By original Census land area, Calhoun County ranks #45 of 46 in South Carolina and #2596 of 3,222 nationally. National rankings include the 50 states, District of Columbia, and Puerto Rico.

Its land area is 0.618 times the South Carolina county-equivalent median of 616.9 square miles. It accounts for 1.3% of the combined county land area in the state.

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

Population and density of Calhoun County

The Census Bureau estimates that 14,188 people lived in Calhoun County on July 1, 2025. That ranks #2,219 of 3,222 county equivalents nationally and #43 of 46 in South Carolina. Since the April 1, 2020 estimates base of 14,120, the population has grown by 68 (+0.5%), compared with +8.8% for South Carolina as a whole.

With 381.1 square miles of land, that is 37 people per square mile (14 per km²), placing Calhoun County #1,821 nationally for density and #40 in South Carolina. The median county equivalent has 47 people per square mile; the South Carolina median is 78. Put another way, there are about 17 acres of land per resident.

Estimated population, 2020–2025 · line scaled to this county’s own range
July 1202020212022202320242025
Estimate14,11114,14114,19714,18914,18614,188
Change—+30+56−8−3+2

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 Calhoun County

2 incorporated places lie at least partly in Calhoun County. Together they are home to 2,194 people (15.5%); the other 11,994 (84.5%) live outside any incorporated place, in unincorporated communities and rural areas.

The largest is St. Matthews town, with 1,827 residents in the county. By land, Cameron town is the largest at 3.14 mi².

Incorporated placePopulation 2025Since 2020Land mi²
St. Matthews townCounty seat1,827−1.3%1.841
Cameron town367−1.6%3.14

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

Metropolitan area

Calhoun County is an outlying county of the Columbia, SC Metropolitan Statistical Area. Its 6 county equivalents have 879,918 residents on 3,703.2 square miles of land; Calhoun County accounts for 10.3% of the land and 1.6% of the residents. By combined land it ranks #79 of 393 metropolitan areas, and #72 by population. It belongs to the Columbia-Sumter-Orangeburg, SC Combined Statistical Area.

County equivalentPopulation 2025Land mi²
Richland County434,956757.3
Lexington County317,588698.5
Kershaw County73,166726.6
Fairfield County20,340686.3
Saluda County19,680453.2
Calhoun County14,188381.1

ZIP codes

7 ZIP Code Tabulation Areas have land in Calhoun County; 2 of them have most of their land inside the county, and the others mainly cover neighboring areas.

29030290472905329112291182913529160

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 Calhoun County

Calhoun County shares a land border with 5 county equivalents. Each of them has more land than Calhoun County. The largest neighbor is Orangeburg County (1,106.4 mi²) and the smallest is Clarendon County (607.2 mi²). Together with its neighbors, Calhoun County forms a block of 4,215.7 mi² of land, of which it holds 9%.

Map of Calhoun County and the 5 county equivalents that border it Orangeburg County, South Carolina: 1,106.4 mi² landRichland County, South Carolina: 757.3 mi² landLexington County, South Carolina: 698.5 mi² landSumter County, South Carolina: 665.1 mi² landClarendon County, South Carolina: 607.2 mi² land
Calhoun 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. CalhounCompare
Orangeburg County1,106.42.9× largerCompare
Richland County757.32× largerCompare
Lexington County698.51.8× largerCompare
Sumter County665.11.7× largerCompare
Clarendon County607.21.6× largerCompare

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

Calhoun County has less land than any of the 50 states. Rhode Island, the smallest state by land area, has 1,033.9 mi², about 2.7 times as much. South Carolina’s county land could hold about 79 areas the size of Calhoun County.

Land area: Calhoun County and the closest-sized states
Calhoun County381.1 mi²
Rhode Island1,033.9 mi²

Another way to picture it: the same land area would fill a square about 19.5 miles (31.4 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 Calhoun County?

Calhoun County has more land than 626 of the other 3,221 county equivalents in the dataset.

Land area compared with the typical county equivalent
Calhoun County381.1 mi²
South Carolina median616.9 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 Calhoun County at #2,630 nationally by total area, 34 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 2.9%, compared with a national county-equivalent median of 1.2% — 1.7 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 Calhoun County in the national ranking. They can be in different states and are not necessarily geographic neighbors.

Land rankCounty equivalentLand mi²Comparison
#2595Carbon County, Pennsylvania381.4Compare
#2596Calhoun County, South Carolina381.1This county
#2597Morgan County, Kentucky381.1Compare

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 33.674637, -80.780425. 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: 987,164,241 m²; AWATER: 29,365,855 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 Calhoun County?

Calhoun County, South Carolina has 381.1 square miles (987.2 km²) of land and 11.3 square miles of water, for a total area of 392.5 square miles. It ranks #2596 of 3,222 U.S. county equivalents by land area.

Is Calhoun County the largest county in South Carolina?

No. Calhoun County ranks #45 of 46 in South Carolina by land area. The largest is Horry County, with 1,133.1 square miles of land.

What counties border Calhoun County?

Calhoun County shares a land border with Orangeburg County, Richland County, Lexington County, Sumter County, and Clarendon County.

What is the population of Calhoun County?

The Census Bureau estimates Calhoun County had 14,188 residents on July 1, 2025, ranking #2,219 of 3,222 county equivalents. That is 37 people per square mile of land.

What is the county seat of Calhoun County?

The county seat of Calhoun County is St. Matthews.

What cities and towns are in Calhoun County?

Calhoun County has 2 incorporated places. The most populous are St. Matthews town and Cameron town; 11,994 residents live outside any incorporated place.

Is Calhoun County part of a metropolitan area?

Yes. It is an outlying county of the Columbia, SC Metropolitan Statistical Area, which has 6 county equivalents and 879,918 residents.

How many ZIP codes are in Calhoun County?

7 ZIP Code Tabulation Areas have land in Calhoun County, and 2 of them have most of their land inside the county. Census ZIP Code Tabulation Areas approximate USPS ZIP Code areas.

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

It has less land than every state. Rhode Island, the smallest, has 2.7 times as much land.

How many acres of land are in Calhoun County?

The land measurement converts to approximately 243,933 acres. Including water, total area is approximately 251,190 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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