County outline
Where Jackson County is located
Area breakdown
Land accounts for 99.2% of Jackson County’s measured area and water for 0.8%. Its combined area converts to 1,331 square kilometers or approximately 328,900 acres.
Green: land · blue: water
| Measurement | Square miles | Square kilometers | Acres |
|---|---|---|---|
| Land | 509.978 | 1,320.837 | 326,385.9 |
| Water | 3.928 | 10.173 | 2,513.9 |
| Total | 513.906 | 1,331.01 | 328,899.8 |
How Jackson County compares
By original Census land area, Jackson County ranks #8 of 92 in Indiana and #2039 of 3,222 nationally. National rankings include the 50 states, District of Columbia, and Puerto Rico.
Its land area is 1.286 times the Indiana county-equivalent median of 396.4 square miles. It accounts for 1.4% of the combined county land area in the state.
See the complete Indiana ranking · What counts as a county equivalent?
Population and density of Jackson County
The Census Bureau estimates that 47,370 people lived in Jackson County on July 1, 2025. That ranks #1,062 of 3,222 county equivalents nationally and #31 of 92 in Indiana. Since the April 1, 2020 estimates base of 46,426, the population has grown by 944 (+2%), compared with +2.8% for Indiana as a whole.
With 510 square miles of land, that is 93 people per square mile (36 per km²), placing Jackson County #1,045 nationally for density and #43 in Indiana. The median county equivalent has 47 people per square mile; the Indiana median is 88. Put another way, there are about 6.9 acres of land per resident.
| July 1 | 2020 | 2021 | 2022 | 2023 | 2024 | 2025 |
|---|---|---|---|---|---|---|
| Estimate | 46,468 | 46,215 | 46,298 | 46,751 | 47,436 | 47,370 |
| Change | — | −253 | +83 | +453 | +685 | −66 |
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 Jackson County
4 incorporated places lie at least partly in Jackson County. Together they are home to 27,751 people (58.6%); the other 19,619 (41.4%) live outside any incorporated place, in unincorporated communities and rural areas.
The largest is Seymour city, with 22,450 residents in the county. The county seat, Brownstown town, has 3,154 residents. Among places with at least 1,000 residents in 2020, Brownstown town grew fastest since then (+4.3%).
| Incorporated place | Population 2025 | Since 2020 | Land mi² |
|---|---|---|---|
| Seymour city | 22,450 | +2.1% | 13.3 |
| Brownstown townCounty seat | 3,154 | +4.3% | 1.619 |
| Crothersville town | 1,506 | 0% | 1.16 |
| Medora town | 641 | −0.2% | 0.304 |
Population: U.S. Census Bureau Vintage 2025 subcounty estimates, counting only the part of each place inside Jackson County. Land: 2026 Census Gazetteer, for the whole place even where it extends into other counties. How communities are listed.
Metropolitan area
Jackson County is a central county of the Seymour, IN Micropolitan Statistical Area. Jackson County is the area’s only county equivalent, so the micro area has the same 510 square miles of land. By combined land it ranks #426 of 542 micropolitan areas, and #247 by population. It belongs to the Indianapolis-Carmel-Muncie, IN Combined Statistical Area.
ZIP codes
8 ZIP Code Tabulation Areas have land in Jackson County; 7 of them have most of their land inside the county, and the others mainly cover neighboring areas.
4710247220472294723547260472644727447281
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 Jackson County
Jackson County shares a land border with 7 county equivalents. It has more land than 6 of them. The largest neighbor is Washington County (513.7 mi²) and the smallest is Scott County (190.4 mi²). Together with its neighbors, Jackson County forms a block of 3,153.3 mi² of land, of which it holds 16.2%.
| Bordering county equivalent | Land mi² | Size vs. Jackson | Compare |
|---|---|---|---|
| Washington County | 513.7 | about the same | Compare |
| Lawrence County | 449.1 | 1.1× smaller | Compare |
| Bartholomew County | 406.9 | 1.3× smaller | Compare |
| Monroe County | 394.5 | 1.3× smaller | Compare |
| Jennings County | 376.6 | 1.4× smaller | Compare |
| Brown County | 312 | 1.6× smaller | Compare |
| Scott County | 190.4 | 2.7× smaller | Compare |
How big is Jackson County compared with U.S. states?
Jackson 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 times as much. Indiana’s county land could hold about 70 areas the size of Jackson County.
Another way to picture it: the same land area would fill a square about 22.6 miles (36.3 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 Jackson County?
Jackson County has more land than 1,183 of the other 3,221 county equivalents in the dataset.
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 Jackson County at #2,124 nationally by total area, 85 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 0.8%, compared with a national county-equivalent median of 1.2% — 0.4 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 Jackson County in the national ranking. They can be in different states and are not necessarily geographic neighbors.
| Land rank | County equivalent | Land mi² | Comparison |
|---|---|---|---|
| #2038 | Braxton County, West Virginia | 510.7 | Compare |
| #2039 | Jackson County, Indiana | 510 | This county |
| #2040 | Floyd County, Georgia | 509.8 | Compare |
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 38.911957, -86.042516. 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: 1,320,837,960 m²; AWATER: 10,172,529 m². Rankings use ALAND; exact ties use ascending GEOID. Tables preserve Census-published square miles to three decimals, with conversions based on those values.
Common questions
How big is Jackson County?
Jackson County, Indiana has 510 square miles (1,320.8 km²) of land and 3.928 square miles of water, for a total area of 513.9 square miles. It ranks #2039 of 3,222 U.S. county equivalents by land area.
Is Jackson County the largest county in Indiana?
No. Jackson County ranks #8 of 92 in Indiana by land area. The largest is Allen County, with 657.1 square miles of land.
What counties border Jackson County?
Jackson County shares a land border with Washington County, Jennings County, Lawrence County, Bartholomew County, Brown County, Scott County, and Monroe County.
What is the population of Jackson County?
The Census Bureau estimates Jackson County had 47,370 residents on July 1, 2025, ranking #1,062 of 3,222 county equivalents. That is 93 people per square mile of land.
What is the county seat of Jackson County?
The county seat of Jackson County is Brownstown.
What cities and towns are in Jackson County?
Jackson County has 4 incorporated places. The most populous are Seymour city, Brownstown town, Crothersville town, and Medora town; 19,619 residents live outside any incorporated place.
Is Jackson County part of a metropolitan area?
Yes. It is a central county of the Seymour, IN Micropolitan Statistical Area.
How many ZIP codes are in Jackson County?
8 ZIP Code Tabulation Areas have land in Jackson County, and 7 of them have most of their land inside the county. Census ZIP Code Tabulation Areas approximate USPS ZIP Code areas.
How does Jackson County compare with U.S. states?
It has less land than every state. Rhode Island, the smallest, has 2 times as much land.
How many acres of land are in Jackson County?
The land measurement converts to approximately 326,386 acres. Including water, total area is approximately 328,900 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.