County outline
Where Pulaski County is located
Area breakdown
Land accounts for 98.1% of Pulaski County’s measured area and water for 1.9%. Its combined area converts to 525.9 square kilometers or approximately 129,945 acres.
Green: land · blue: water
| Measurement | Square miles | Square kilometers | Acres |
|---|---|---|---|
| Land | 199.269 | 516.104 | 127,532.2 |
| Water | 3.77 | 9.764 | 2,412.8 |
| Total | 203.039 | 525.869 | 129,945 |
How Pulaski County compares
By original Census land area, Pulaski County ranks #100 of 102 in Illinois and #2997 of 3,222 nationally. National rankings include the 50 states, District of Columbia, and Puerto Rico.
Its land area is 0.39 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 Pulaski County
The Census Bureau estimates that 4,820 people lived in Pulaski County on July 1, 2025. That ranks #2,904 of 3,222 county equivalents nationally and #97 of 102 in Illinois. Since the April 1, 2020 estimates base of 5,206, the population has declined by 386 (−7.4%), compared with −0.8% for Illinois as a whole.
With 199.3 square miles of land, that is 24 people per square mile (9.3 per km²), placing Pulaski County #2,165 nationally for density and #83 in Illinois. The median county equivalent has 47 people per square mile; the Illinois median is 44. Put another way, there are about 26 acres of land per resident.
| July 1 | 2020 | 2021 | 2022 | 2023 | 2024 | 2025 |
|---|---|---|---|---|---|---|
| Estimate | 5,176 | 5,092 | 4,963 | 4,967 | 4,883 | 4,820 |
| Change | — | −84 | −129 | +4 | −84 | −63 |
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 Pulaski County
7 incorporated places lie at least partly in Pulaski County. Together they are home to 2,478 people (51.4%); the other 2,342 (48.6%) live outside any incorporated place, in unincorporated communities and rural areas.
The largest is Mounds city, with 600 residents in the county. The county seat, Mound City city, has 477 residents. By land, Olmsted village is the largest at 3.365 mi².
| Incorporated place | Population 2025 | Since 2020 | Land mi² |
|---|---|---|---|
| Mounds city | 600 | −8.8% | 1.208 |
| Mound City cityCounty seat | 477 | −9% | 0.675 |
| Ullin village | 457 | −5% | 2.811 |
| Karnak village | 394 | −7.3% | 1.806 |
| Olmsted village | 265 | −7.3% | 3.365 |
| New Grand Chain village | 143 | −7.7% | 1.043 |
| Pulaski village | 142 | −8.4% | 1.31 |
Population: U.S. Census Bureau Vintage 2025 subcounty estimates, counting only the part of each place inside Pulaski County. Land: 2026 Census Gazetteer, for the whole place even where it extends into other counties. How communities are listed.
Metropolitan area
Pulaski 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
10 ZIP Code Tabulation Areas have land in Pulaski County; 7 of them have most of their land inside the county, and the others mainly cover neighboring areas.
62923629266294162956629636296462970629766299262996
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 Pulaski County
Pulaski County shares a land border with 6 county equivalents, including 2 in Kentucky. Each of them has more land than Pulaski County. The largest neighbor is Union County (413.4 mi²) and the smallest is Alexander County (235.4 mi²). Together with its neighbors, Pulaski County forms a block of 1,924.9 mi² of land, of which it holds 10.4%.
| Bordering county equivalent | Land mi² | Size vs. Pulaski | Compare |
|---|---|---|---|
| Union County | 413.4 | 2.1× larger | Compare |
| Johnson County | 343.7 | 1.7× larger | Compare |
| McCracken CountyKentucky | 248.8 | 1.2× larger | Compare |
| Ballard CountyKentucky | 247.1 | 1.2× larger | Compare |
| Massac County | 237.2 | 1.2× larger | Compare |
| Alexander County | 235.4 | 1.2× larger | Compare |
How big is Pulaski County compared with U.S. states?
Pulaski County has less land than any of the 50 states. Rhode Island, the smallest state by land area, has 1,033.9 mi², about 5.2 times as much. Illinois’s county land could hold about 279 areas the size of Pulaski County.
Another way to picture it: the same land area would fill a square about 14.1 miles (22.7 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 Pulaski County?
Pulaski County has more land than 225 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 Pulaski County at #3,018 nationally by total area, 21 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 Pulaski County in the national ranking. They can be in different states and are not necessarily geographic neighbors.
| Land rank | County equivalent | Land mi² | Comparison |
|---|---|---|---|
| #2996 | Treutlen County, Georgia | 199.4 | Compare |
| #2997 | Pulaski County, Illinois | 199.3 | This county |
| #2998 | Owsley County, Kentucky | 197.4 | 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 37.215615, -89.127755. 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: 516,105,482 m²; AWATER: 9,763,459 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 Pulaski County?
Pulaski County, Illinois has 199.3 square miles (516.1 km²) of land and 3.77 square miles of water, for a total area of 203 square miles. It ranks #2997 of 3,222 U.S. county equivalents by land area.
Is Pulaski County the largest county in Illinois?
No. Pulaski County ranks #100 of 102 in Illinois by land area. The largest is McLean County, with 1,183.2 square miles of land.
What counties border Pulaski County?
Pulaski County shares a land border with Alexander County, Ballard County, Kentucky, Union County, Johnson County, Massac County, and McCracken County, Kentucky.
What is the population of Pulaski County?
The Census Bureau estimates Pulaski County had 4,820 residents on July 1, 2025, ranking #2,904 of 3,222 county equivalents. That is 24 people per square mile of land.
What is the county seat of Pulaski County?
The county seat of Pulaski County is Mound City.
What cities and towns are in Pulaski County?
Pulaski County has 7 incorporated places. The most populous five are Mounds city, Mound City city, Ullin village, Karnak village, and Olmsted village; 2,342 residents live outside any incorporated place.
Is Pulaski County part of a metropolitan area?
No. Pulaski County is outside every metropolitan and micropolitan statistical area in the July 2023 OMB delineation.
How many ZIP codes are in Pulaski County?
10 ZIP Code Tabulation Areas have land in Pulaski 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 Pulaski County compare with U.S. states?
It has less land than every state. Rhode Island, the smallest, has 5.2 times as much land.
How many acres of land are in Pulaski County?
The land measurement converts to approximately 127,532 acres. Including water, total area is approximately 129,945 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.