Brown County area

Brown County, Ohio covers 493 square miles: 489.6 square miles of land and 3.42 square miles of water. Its county seat is Georgetown. An estimated 44,397 people lived there in 2025.

Official Census measurements · GEOID 390152026 Gazetteer · retrieved September 27, 2026
Land area489.6 mi²
Water area3.42 mi²
Population (2025)44,397
People per mi²91

County outline

Generalized outline of Brown County, Ohio
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 Brown County is located

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

Area breakdown

Land accounts for 99.3% of Brown County’s measured area and water for 0.7%. Its combined area converts to 1,276.8 square kilometers or approximately 315,501 acres.

Green: land · blue: water

MeasurementSquare milesSquare kilometersAcres
Land489.5511,267.931313,312.6
Water3.428.8582,188.8
Total492.9711,276.789315,501.4

How Brown County compares

By original Census land area, Brown County ranks #29 of 88 in Ohio and #2127 of 3,222 nationally. National rankings include the 50 states, District of Columbia, and Puerto Rico.

Its land area is 1.123 times the Ohio county-equivalent median of 436 square miles. It accounts for 1.2% of the combined county land area in the state.

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

Population and density of Brown County

The Census Bureau estimates that 44,397 people lived in Brown County on July 1, 2025. That ranks #1,126 of 3,222 county equivalents nationally and #55 of 88 in Ohio. Since the April 1, 2020 estimates base of 43,681, the population has grown by 716 (+1.6%), compared with +0.9% for Ohio as a whole.

With 489.6 square miles of land, that is 91 people per square mile (35 per km²), placing Brown County #1,065 nationally for density and #61 in Ohio. The median county equivalent has 47 people per square mile; the Ohio median is 120. Put another way, there are about 7.1 acres of land per resident.

Estimated population, 2020–2025 · line scaled to this county’s own range
July 1202020212022202320242025
Estimate43,68443,68543,65543,77144,16344,397
Change—+1−30+116+392+234

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 Brown County

9 incorporated places lie at least partly in Brown County. Together they are home to 14,705 people (33.1%); the other 29,692 (66.9%) live outside any incorporated place, in unincorporated communities and rural areas.

The largest is Georgetown village, with 4,450 residents in the county. By land, Mount Orab village is the largest at 9.679 mi². Among places with at least 1,000 residents in 2020, Aberdeen village grew fastest since then (+2.2%).

Incorporated placePopulation 2025Since 2020Land mi²
Georgetown villageCounty seat4,450−0.1%4.177
Mount Orab village4,418+1.5%9.679
Ripley village1,597+1.3%1.993
Aberdeen village1,551+2.2%1.35
Sardinia villageAlso in 1 other county1,101+1.9%1.754
Russellville village548+1.5%0.729
Hamersville village503+1.4%0.438
Fayetteville village318+0.6%0.472
Higginsport village219+1.4%0.251

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

Metropolitan area

Brown County is an outlying county of the Cincinnati, OH-KY-IN Metropolitan Statistical Area. Its 15 county equivalents have 2,312,858 residents on 4,385.2 square miles of land; Brown County accounts for 11.2% of the land and 1.9% of the residents. By combined land it ranks #60 of 393 metropolitan areas, and #30 by population. It belongs to the Cincinnati-Wilmington, OH-KY-IN Combined Statistical Area.

County equivalentPopulation 2025Land mi²
Hamilton County838,418405.5
Butler County400,128466.5
Warren County257,181401.4
Clermont County216,977452.6
Kenton CountyKentucky175,779160.4
Boone CountyKentucky145,316246.3
Campbell CountyKentucky95,441151.3
Dearborn CountyIndiana51,609305.1
Brown County44,397489.6
Grant CountyKentucky26,181258
Franklin CountyIndiana23,286384.4
Pendleton CountyKentucky14,800277.1
Gallatin CountyKentucky8,84098.3
Bracken CountyKentucky8,511202.7
Ohio CountyIndiana5,99486.2

ZIP codes

20 ZIP Code Tabulation Areas have land in Brown County; 11 of them have most of their land inside the county, and the others mainly cover neighboring areas.

4510145106451074511545118451194512045121451304513145133451424514445148451544516745168451714517645697

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 Brown County

Brown County shares a land border with 6 county equivalents, including 2 in Kentucky. It has more land than 4 of them. The largest neighbor is Adams County (583.9 mi²) and the smallest is Bracken County (202.7 mi²). Together with its neighbors, Brown County forms a block of 2,930.6 mi² of land, of which it holds 16.7%.

Map of Brown County and the 6 county equivalents that border it Clermont County, Ohio: 452.6 mi² landAdams County, Ohio: 583.9 mi² landHighland County, Ohio: 553.1 mi² landMason County, Kentucky: 240.1 mi² landBracken County, Kentucky: 202.7 mi² landClinton County, Ohio: 408.7 mi² land
Brown 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. BrownCompare
Adams County583.91.2× largerCompare
Highland County553.11.1× largerCompare
Clermont County452.61.1× smallerCompare
Clinton County408.71.2× smallerCompare
Mason CountyKentucky240.12× smallerCompare
Bracken CountyKentucky202.72.4× smallerCompare

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

Brown County has less land than any of the 50 states. Rhode Island, the smallest state by land area, has 1,033.9 mi², about 2.1 times as much. Ohio’s county land could hold about 83 areas the size of Brown County.

Land area: Brown County and the closest-sized states
Brown County489.6 mi²
Rhode Island1,033.9 mi²

Another way to picture it: the same land area would fill a square about 22.1 miles (35.6 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 Brown County?

Brown County has more land than 1,095 of the other 3,221 county equivalents in the dataset.

Land area compared with the typical county equivalent
Brown County489.6 mi²
Ohio median436 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 Brown County at #2,210 nationally by total area, 83 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 0.7%, compared with a national county-equivalent median of 1.2% — 0.5 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 Brown County in the national ranking. They can be in different states and are not necessarily geographic neighbors.

Land rankCounty equivalentLand mi²Comparison
#2126Dickson County, Tennessee489.9Compare
#2127Brown County, Ohio489.6This county
#2128Marion County, South Carolina489.4Compare

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 38.931377, -83.866772. 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: 1,267,932,476 m²; AWATER: 8,858,346 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 Brown County?

Brown County, Ohio has 489.6 square miles (1,267.9 km²) of land and 3.42 square miles of water, for a total area of 493 square miles. It ranks #2127 of 3,222 U.S. county equivalents by land area.

Is Brown County the largest county in Ohio?

No. Brown County ranks #29 of 88 in Ohio by land area. The largest is Ashtabula County, with 702.4 square miles of land.

What counties border Brown County?

Brown County shares a land border with Clermont County, Adams County, Highland County, Mason County, Kentucky, Bracken County, Kentucky, and Clinton County.

What is the population of Brown County?

The Census Bureau estimates Brown County had 44,397 residents on July 1, 2025, ranking #1,126 of 3,222 county equivalents. That is 91 people per square mile of land.

What is the county seat of Brown County?

The county seat of Brown County is Georgetown.

What cities and towns are in Brown County?

Brown County has 9 incorporated places. The most populous five are Georgetown village, Mount Orab village, Ripley village, Aberdeen village, and Sardinia village; 29,692 residents live outside any incorporated place.

Is Brown County part of a metropolitan area?

Yes. It is an outlying county of the Cincinnati, OH-KY-IN Metropolitan Statistical Area, which has 15 county equivalents and 2,312,858 residents.

How many ZIP codes are in Brown County?

20 ZIP Code Tabulation Areas have land in Brown County, and 11 of them have most of their land inside the county. Census ZIP Code Tabulation Areas approximate USPS ZIP Code areas.

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

It has less land than every state. Rhode Island, the smallest, has 2.1 times as much land.

How many acres of land are in Brown County?

The land measurement converts to approximately 313,313 acres. Including water, total area is approximately 315,501 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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