County outline
Where Wabash County is located
Area breakdown
Land accounts for 98.1% of Wabash County’s measured area and water for 1.9%. Its combined area converts to 589.4 square kilometers or approximately 145,638 acres.
Green: land · blue: water
| Measurement | Square miles | Square kilometers | Acres |
|---|---|---|---|
| Land | 223.323 | 578.404 | 142,926.7 |
| Water | 4.237 | 10.974 | 2,711.7 |
| Total | 227.56 | 589.378 | 145,638.4 |
How Wabash County compares
By original Census land area, Wabash County ranks #98 of 102 in Illinois and #2963 of 3,222 nationally. National rankings include the 50 states, District of Columbia, and Puerto Rico.
Its land area is 0.437 times the Illinois county-equivalent median of 510.7 square miles. It accounts for 0.4% of the combined county land area in the state.
See the complete Illinois ranking · What counts as a county equivalent?
Population and density of Wabash County
The Census Bureau estimates that 10,907 people lived in Wabash County on July 1, 2025. That ranks #2,421 of 3,222 county equivalents nationally and #86 of 102 in Illinois. Since the April 1, 2020 estimates base of 11,361, the population has declined by 454 (−4%), compared with −0.8% for Illinois as a whole.
With 223.3 square miles of land, that is 49 people per square mile (19 per km²), placing Wabash County #1,577 nationally for density and #46 in Illinois. The median county equivalent has 47 people per square mile; the Illinois median is 44. Put another way, there are about 13 acres of land per resident.
| July 1 | 2020 | 2021 | 2022 | 2023 | 2024 | 2025 |
|---|---|---|---|---|---|---|
| Estimate | 11,319 | 11,224 | 11,061 | 11,065 | 11,026 | 10,907 |
| Change | — | −95 | −163 | +4 | −39 | −119 |
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 Wabash County
4 incorporated places lie at least partly in Wabash County. Together they are home to 7,571 people (69.4%); the other 3,336 (30.6%) live outside any incorporated place, in unincorporated communities and rural areas.
The largest is Mount Carmel city, with 6,723 residents in the county.
| Incorporated place | Population 2025 | Since 2020 | Land mi² |
|---|---|---|---|
| Mount Carmel cityCounty seat | 6,723 | −4% | 4.809 |
| Allendale village | 437 | −4% | 0.307 |
| Bellmont village | 241 | −3.2% | 0.325 |
| Keensburg village | 170 | −4% | 0.26 |
Population: U.S. Census Bureau Vintage 2025 subcounty estimates, counting only the part of each place inside Wabash County. Land: 2026 Census Gazetteer, for the whole place even where it extends into other counties. How communities are listed.
Metropolitan area
Wabash 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
7 ZIP Code Tabulation Areas have land in Wabash County; 4 of them have most of their land inside the county, and the others mainly cover neighboring areas.
62410624606247662811628186285262863
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 Wabash County
Wabash County shares a land border with 6 county equivalents, including 2 in Indiana. It has more land than 1 of them. The largest neighbor is Knox County (515.8 mi²) and the smallest is Edwards County (222.4 mi²). Together with its neighbors, Wabash County forms a block of 2,676.1 mi² of land, of which it holds 8.3%.
| Bordering county equivalent | Land mi² | Size vs. Wabash | Compare |
|---|---|---|---|
| Knox CountyIndiana | 515.8 | 2.3× larger | Compare |
| White County | 495 | 2.2× larger | Compare |
| Gibson CountyIndiana | 487.4 | 2.2× larger | Compare |
| Lawrence County | 372.2 | 1.7× larger | Compare |
| Richland County | 360 | 1.6× larger | Compare |
| Edwards County | 222.4 | about the same | Compare |
How big is Wabash County compared with U.S. states?
Wabash County has less land than any of the 50 states. Rhode Island, the smallest state by land area, has 1,033.9 mi², about 4.6 times as much. Illinois’s county land could hold about 249 areas the size of Wabash County.
Another way to picture it: the same land area would fill a square about 14.9 miles (24.1 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 Wabash County?
Wabash County has more land than 259 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 Wabash County at #2,985 nationally by total area, 22 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 1.9%, compared with a national county-equivalent median of 1.2% — 0.7 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 Wabash County in the national ranking. They can be in different states and are not necessarily geographic neighbors.
| Land rank | County equivalent | Land mi² | Comparison |
|---|---|---|---|
| #2962 | Union County, Tennessee | 223.6 | Compare |
| #2963 | Wabash County, Illinois | 223.3 | This county |
| #2964 | Edwards County, Illinois | 222.4 | 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 38.445821, -87.839167. 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: 578,403,984 m²; AWATER: 10,973,568 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 Wabash County?
Wabash County, Illinois has 223.3 square miles (578.4 km²) of land and 4.237 square miles of water, for a total area of 227.6 square miles. It ranks #2963 of 3,222 U.S. county equivalents by land area.
Is Wabash County the largest county in Illinois?
No. Wabash County ranks #98 of 102 in Illinois by land area. The largest is McLean County, with 1,183.2 square miles of land.
What counties border Wabash County?
Wabash County shares a land border with Edwards County, Gibson County, Indiana, Lawrence County, Knox County, Indiana, Richland County, and White County.
What is the population of Wabash County?
The Census Bureau estimates Wabash County had 10,907 residents on July 1, 2025, ranking #2,421 of 3,222 county equivalents. That is 49 people per square mile of land.
What is the county seat of Wabash County?
The county seat of Wabash County is Mount Carmel.
What cities and towns are in Wabash County?
Wabash County has 4 incorporated places. The most populous are Mount Carmel city, Allendale village, Bellmont village, and Keensburg village; 3,336 residents live outside any incorporated place.
Is Wabash County part of a metropolitan area?
No. Wabash County is outside every metropolitan and micropolitan statistical area in the July 2023 OMB delineation.
How many ZIP codes are in Wabash County?
7 ZIP Code Tabulation Areas have land in Wabash County, and 4 of them have most of their land inside the county. Census ZIP Code Tabulation Areas approximate USPS ZIP Code areas.
How does Wabash County compare with U.S. states?
It has less land than every state. Rhode Island, the smallest, has 4.6 times as much land.
How many acres of land are in Wabash County?
The land measurement converts to approximately 142,927 acres. Including water, total area is approximately 145,638 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.