Jackson County area

Jackson County, Illinois covers 602.2 square miles: 583.6 square miles of land and 18.7 square miles of water. Its county seat is Murphysboro. An estimated 52,501 people lived there in 2025.

Official Census measurements · GEOID 170772026 Gazetteer · retrieved September 27, 2026
Land area583.6 mi²
Water area18.7 mi²
Population (2025)52,501
People per mi²90

County outline

Generalized outline of Jackson County, Illinois
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 Jackson County is located

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

Area breakdown

Land accounts for 96.9% of Jackson County’s measured area and water for 3.1%. Its combined area converts to 1,559.8 square kilometers or approximately 385,423 acres.

Green: land · blue: water

MeasurementSquare milesSquare kilometersAcres
Land583.5741,511.45373,487.4
Water18.6548.30311,936
Total602.2241,559.753385,423.4

How Jackson County compares

By original Census land area, Jackson County ranks #37 of 102 in Illinois and #1686 of 3,222 nationally. National rankings include the 50 states, District of Columbia, and Puerto Rico.

Its land area is 1.143 times the Illinois county-equivalent median of 510.7 square miles. It accounts for 1.1% of the combined county land area in the state.

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

Population and density of Jackson County

The Census Bureau estimates that 52,501 people lived in Jackson County on July 1, 2025. That ranks #993 of 3,222 county equivalents nationally and #27 of 102 in Illinois. Since the April 1, 2020 estimates base of 53,347, the population has declined by 846 (−1.6%), compared with −0.8% for Illinois as a whole.

With 583.6 square miles of land, that is 90 people per square mile (35 per km²), placing Jackson County #1,075 nationally for density and #27 in Illinois. The median county equivalent has 47 people per square mile; the Illinois median is 44. 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
Estimate53,28953,05652,72952,50752,68252,501
Change—−233−327−222+175−181

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

11 incorporated places lie at least partly in Jackson County. Together they are home to 33,639 people (64.1%); the other 18,862 (35.9%) live outside any incorporated place, in unincorporated communities and rural areas.

The largest is Carbondale city, with 21,811 residents in the county (the city extends into 1 other county). The county seat, Murphysboro city, has 6,977 residents.

Incorporated placePopulation 2025Since 2020Land mi²
Carbondale cityAlso in 1 other county21,811−2.2%17.5
Murphysboro cityCounty seat6,977−1.6%5.247
De Soto village1,388−1.1%0.912
Elkville village831−1.4%0.767
Ava city542−1.1%1.057
Makanda village542−1.1%5.281
Grand Tower city474−1.3%1.248
Dowell village364−1.6%0.39
Campbell Hill village308−1.9%0.462
Vergennes village234−0.4%0.352
Gorham village168−1.2%1.219

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 Carbondale, IL Micropolitan Statistical Area. Jackson County is the area’s only county equivalent, so the micro area has the same 583.6 square miles of land. By combined land it ranks #366 of 542 micropolitan areas, and #210 by population. It belongs to the Carbondale-Marion-Herrin, IL Combined Statistical Area.

ZIP codes

22 ZIP Code Tabulation Areas have land in Jackson County; 13 of them have most of their land inside the county, and the others mainly cover neighboring areas.

62272622746228062832629016290262903629056290762916629186292062924629276293262940629426295062958629666297562994

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 6 county equivalents, including 1 in Missouri. It has more land than every one of them. The largest neighbor is Randolph County (575.4 mi²) and the smallest is Franklin County (408.9 mi²). Together with its neighbors, Jackson County forms a block of 3,317.8 mi² of land, of which it holds 17.6%.

Map of Jackson County and the 6 county equivalents that border it Perry County, Illinois: 441.9 mi² landUnion County, Illinois: 413.4 mi² landPerry County, Missouri: 474.4 mi² landWilliamson County, Illinois: 420.2 mi² landRandolph County, Illinois: 575.4 mi² landFranklin County, Illinois: 408.9 mi² land
Jackson 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. JacksonCompare
Randolph County575.4about the sameCompare
Perry CountyMissouri474.41.2× smallerCompare
Perry County441.91.3× smallerCompare
Williamson County420.21.4× smallerCompare
Union County413.41.4× smallerCompare
Franklin County408.91.4× smallerCompare

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 1.8 times as much. Illinois’s county land could hold about 95 areas the size of Jackson County.

Land area: Jackson County and the closest-sized states
Jackson County583.6 mi²
Rhode Island1,033.9 mi²

Another way to picture it: the same land area would fill a square about 24.2 miles (38.9 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 1,536 of the other 3,221 county equivalents in the dataset.

Land area compared with the typical county equivalent
Jackson County583.6 mi²
Illinois median510.7 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 Jackson County at #1,736 nationally by total area, 50 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 3.1%, compared with a national county-equivalent median of 1.2% — 1.9 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 Jackson County in the national ranking. They can be in different states and are not necessarily geographic neighbors.

Land rankCounty equivalentLand mi²Comparison
#1685Adams County, Ohio583.9Compare
#1686Jackson County, Illinois583.6This county
#1687Upshur County, Texas583Compare

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 37.786096, -89.381212. 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: 1,511,448,963 m²; AWATER: 48,302,862 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 Jackson County?

Jackson County, Illinois has 583.6 square miles (1,511.4 km²) of land and 18.7 square miles of water, for a total area of 602.2 square miles. It ranks #1686 of 3,222 U.S. county equivalents by land area.

Is Jackson County the largest county in Illinois?

No. Jackson County ranks #37 of 102 in Illinois by land area. The largest is McLean County, with 1,183.2 square miles of land.

What counties border Jackson County?

Jackson County shares a land border with Perry County, Union County, Perry County, Missouri, Williamson County, Randolph County, and Franklin County.

What is the population of Jackson County?

The Census Bureau estimates Jackson County had 52,501 residents on July 1, 2025, ranking #993 of 3,222 county equivalents. That is 90 people per square mile of land.

What is the county seat of Jackson County?

The county seat of Jackson County is Murphysboro.

What cities and towns are in Jackson County?

Jackson County has 11 incorporated places. The most populous five are Carbondale city, Murphysboro city, De Soto village, Elkville village, and Ava city; 18,862 residents live outside any incorporated place.

Is Jackson County part of a metropolitan area?

Yes. It is a central county of the Carbondale, IL Micropolitan Statistical Area.

How many ZIP codes are in Jackson County?

22 ZIP Code Tabulation Areas have land in Jackson County, and 13 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 1.8 times as much land.

How many acres of land are in Jackson County?

The land measurement converts to approximately 373,487 acres. Including water, total area is approximately 385,423 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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