Clinton County area

Clinton County, Indiana covers 405.2 square miles: 405.1 square miles of land and 0.178 square miles of water. Its county seat is Frankfort. An estimated 33,322 people lived there in 2025.

Official Census measurements · GEOID 180232026 Gazetteer · retrieved September 27, 2026
Land area405.1 mi²
Water area0.178 mi²
Population (2025)33,322
People per mi²82

County outline

Generalized outline of Clinton County, Indiana
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 Clinton County is located

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

Area breakdown

Land accounts for 100% of Clinton County’s measured area and water for 0%. Its combined area converts to 1,049.6 square kilometers or approximately 259,357 acres.

Green: land · blue: water

MeasurementSquare milesSquare kilometersAcres
Land405.0671,049.119259,242.9
Water0.1780.461113.9
Total405.2451,049.58259,356.8

How Clinton County compares

By original Census land area, Clinton County ranks #40 of 92 in Indiana and #2501 of 3,222 nationally. National rankings include the 50 states, District of Columbia, and Puerto Rico.

Its land area is 1.022 times the Indiana county-equivalent median of 396.4 square miles. It accounts for 1.1% of the combined county land area in the state.

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

Population and density of Clinton County

The Census Bureau estimates that 33,322 people lived in Clinton County on July 1, 2025. That ranks #1,397 of 3,222 county equivalents nationally and #50 of 92 in Indiana. Since the April 1, 2020 estimates base of 33,195, the population has grown by 127 (+0.4%), compared with +2.8% for Indiana as a whole.

With 405.1 square miles of land, that is 82 people per square mile (32 per km²), placing Clinton County #1,132 nationally for density and #48 in Indiana. The median county equivalent has 47 people per square mile; the Indiana median is 88. Put another way, there are about 7.8 acres of land per resident.

Estimated population, 2020–2025 · line scaled to this county’s own range
July 1202020212022202320242025
Estimate33,18532,99432,87033,09133,30733,322
Change—−191−124+221+216+15

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 Clinton County

6 incorporated places lie at least partly in Clinton County. Together they are home to 21,447 people (64.4%); the other 11,875 (35.6%) live outside any incorporated place, in unincorporated communities and rural areas.

The largest is Frankfort city, with 16,837 residents in the county. Among places with at least 1,000 residents in 2020, Rossville town grew fastest since then (+1.5%).

Incorporated placePopulation 2025Since 2020Land mi²
Frankfort cityCounty seat16,837−0.3%9.844
Rossville town1,525+1.5%0.459
Mulberry town1,224−0.6%0.534
Kirklin town717+1.3%0.417
Colfax town714+1.3%0.37
Michigantown town430−1.4%0.277

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

Metropolitan area

Clinton County is a central county of the Frankfort, IN Micropolitan Statistical Area. Clinton County is the area’s only county equivalent, so the micro area has the same 405.1 square miles of land. By combined land it ranks #485 of 542 micropolitan areas, and #412 by population. It belongs to the Lafayette-West Lafayette-Frankfort, IN Combined Statistical Area.

ZIP codes

12 ZIP Code Tabulation Areas have land in Clinton County; 6 of them have most of their land inside the county, and the others mainly cover neighboring areas.

460354603946041460494605046057460584606546069469794790547930

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 Clinton County

Clinton County shares a land border with 7 county equivalents. It has more land than 4 of them. The largest neighbor is Montgomery County (504.6 mi²) and the smallest is Tipton County (260.5 mi²). Together with its neighbors, Clinton County forms a block of 3,151.7 mi² of land, of which it holds 12.9%.

Map of Clinton County and the 7 county equivalents that border it Boone County, Indiana: 422.9 mi² landCarroll County, Indiana: 372.2 mi² landTippecanoe County, Indiana: 498.9 mi² landTipton County, Indiana: 260.5 mi² landHoward County, Indiana: 293.1 mi² landMontgomery County, Indiana: 504.6 mi² landHamilton County, Indiana: 394.4 mi² land
Clinton 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. ClintonCompare
Montgomery County504.61.2× largerCompare
Tippecanoe County498.91.2× largerCompare
Boone County422.9about the sameCompare
Hamilton County394.4about the sameCompare
Carroll County372.21.1× smallerCompare
Howard County293.11.4× smallerCompare
Tipton County260.51.6× smallerCompare

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

Clinton County has less land than any of the 50 states. Rhode Island, the smallest state by land area, has 1,033.9 mi², about 2.6 times as much. Indiana’s county land could hold about 88 areas the size of Clinton County.

Land area: Clinton County and the closest-sized states
Clinton County405.1 mi²
Rhode Island1,033.9 mi²

Another way to picture it: the same land area would fill a square about 20.1 miles (32.4 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 Clinton County?

Clinton County has more land than 721 of the other 3,221 county equivalents in the dataset.

Land area compared with the typical county equivalent
Clinton County405.1 mi²
Indiana median396.4 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 Clinton County at #2,574 nationally by total area, 73 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 0%, compared with a national county-equivalent median of 1.2% — 1.1 percentage points lower. 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 Clinton County in the national ranking. They can be in different states and are not necessarily geographic neighbors.

Land rankCounty equivalentLand mi²Comparison
#2500Dillon County, South Carolina405.1Compare
#2501Clinton County, Indiana405.1This county
#2502Quitman County, Mississippi405Compare

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 40.305944, -86.477567. 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: 1,049,119,183 m²; AWATER: 461,117 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 Clinton County?

Clinton County, Indiana has 405.1 square miles (1,049.1 km²) of land and 0.178 square miles of water, for a total area of 405.2 square miles. It ranks #2501 of 3,222 U.S. county equivalents by land area.

Is Clinton County the largest county in Indiana?

No. Clinton County ranks #40 of 92 in Indiana by land area. The largest is Allen County, with 657.1 square miles of land.

What counties border Clinton County?

Clinton County shares a land border with Boone County, Carroll County, Tippecanoe County, Tipton County, Howard County, Montgomery County, and Hamilton County.

What is the population of Clinton County?

The Census Bureau estimates Clinton County had 33,322 residents on July 1, 2025, ranking #1,397 of 3,222 county equivalents. That is 82 people per square mile of land.

What is the county seat of Clinton County?

The county seat of Clinton County is Frankfort.

What cities and towns are in Clinton County?

Clinton County has 6 incorporated places. The most populous five are Frankfort city, Rossville town, Mulberry town, Kirklin town, and Colfax town; 11,875 residents live outside any incorporated place.

Is Clinton County part of a metropolitan area?

Yes. It is a central county of the Frankfort, IN Micropolitan Statistical Area.

How many ZIP codes are in Clinton County?

12 ZIP Code Tabulation Areas have land in Clinton County, and 6 of them have most of their land inside the county. Census ZIP Code Tabulation Areas approximate USPS ZIP Code areas.

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

It has less land than every state. Rhode Island, the smallest, has 2.6 times as much land.

How many acres of land are in Clinton County?

The land measurement converts to approximately 259,243 acres. Including water, total area is approximately 259,357 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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