County outline
Where Des Moines County is located
Area breakdown
Land accounts for 96.8% of Des Moines County’s measured area and water for 3.2%. Its combined area converts to 1,113.1 square kilometers or approximately 275,056 acres.
Green: land · blue: water
| Measurement | Square miles | Square kilometers | Acres |
|---|---|---|---|
| Land | 416.129 | 1,077.769 | 266,322.6 |
| Water | 13.646 | 35.343 | 8,733.4 |
| Total | 429.775 | 1,113.112 | 275,056 |
How Des Moines County compares
By original Census land area, Des Moines County ranks #93 of 99 in Iowa and #2429 of 3,222 nationally. National rankings include the 50 states, District of Columbia, and Puerto Rico.
Its land area is 0.731 times the Iowa county-equivalent median of 569.6 square miles. It accounts for 0.7% of the combined county land area in the state.
See the complete Iowa ranking · What counts as a county equivalent?
Population and density of Des Moines County
The Census Bureau estimates that 38,077 people lived in Des Moines County on July 1, 2025. That ranks #1,261 of 3,222 county equivalents nationally and #17 of 99 in Iowa. Since the April 1, 2020 estimates base of 38,935, the population has declined by 858 (−2.2%), compared with +1.5% for Iowa as a whole.
With 416.1 square miles of land, that is 92 people per square mile (35 per km²), placing Des Moines County #1,061 nationally for density and #13 in Iowa. The median county equivalent has 47 people per square mile; the Iowa median is 26. Put another way, there are about 7 acres of land per resident.
| July 1 | 2020 | 2021 | 2022 | 2023 | 2024 | 2025 |
|---|---|---|---|---|---|---|
| Estimate | 38,849 | 38,537 | 38,229 | 38,299 | 38,150 | 38,077 |
| Change | — | −312 | −308 | +70 | −149 | −73 |
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 Des Moines County
5 incorporated places lie at least partly in Des Moines County. Together they are home to 29,611 people (77.8%); the other 8,466 (22.2%) live outside any incorporated place, in unincorporated communities and rural areas.
The largest is Burlington city, with 23,336 residents in the county. Among places with at least 1,000 residents in 2020, West Burlington city grew fastest since then (+4.9%).
| Incorporated place | Population 2025 | Since 2020 | Land mi² |
|---|---|---|---|
| Burlington cityCounty seat | 23,336 | −2.8% | 14.4 |
| West Burlington city | 3,358 | +4.9% | 4.837 |
| Mediapolis city | 1,660 | −1.5% | 1.205 |
| Danville city | 896 | −6% | 0.749 |
| Middletown city | 361 | −1.1% | 0.549 |
Population: U.S. Census Bureau Vintage 2025 subcounty estimates, counting only the part of each place inside Des Moines County. Land: 2026 Census Gazetteer, for the whole place even where it extends into other counties. How communities are listed.
Metropolitan area
Des Moines County is a central county of the Burlington, IA-IL Micropolitan Statistical Area. Its 2 county equivalents have 44,061 residents on 794.9 square miles of land; Des Moines County accounts for 52.3% of the land and 86.4% of the residents. By combined land it ranks #267 of 542 micropolitan areas, and #284 by population. It belongs to the Burlington-Fort Madison, IA-IL Combined Statistical Area.
| County equivalent | Population 2025 | Land mi² |
|---|---|---|
| Des Moines County | 38,077 | 416.1 |
| Henderson CountyIllinois | 5,984 | 378.8 |
ZIP codes
12 ZIP Code Tabulation Areas have land in Des Moines County; 8 of them have most of their land inside the county, and the others mainly cover neighboring areas.
526015262352637526385264052644526455264652650526555265852660
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 Des Moines County
Des Moines County shares a land border with 5 county equivalents, including 2 in Illinois. It has more land than 2 of them. The largest neighbor is Mercer County (561.2 mi²) and the smallest is Henderson County (378.8 mi²). Together with its neighbors, Des Moines County forms a block of 2,709.8 mi² of land, of which it holds 15.4%.
| Bordering county equivalent | Land mi² | Size vs. Des Moines | Compare |
|---|---|---|---|
| Mercer CountyIllinois | 561.2 | 1.3× larger | Compare |
| Lee County | 517.6 | 1.2× larger | Compare |
| Henry County | 434.3 | about the same | Compare |
| Louisa County | 401.8 | about the same | Compare |
| Henderson CountyIllinois | 378.8 | 1.1× smaller | Compare |
How big is Des Moines County compared with U.S. states?
Des Moines County has less land than any of the 50 states. Rhode Island, the smallest state by land area, has 1,033.9 mi², about 2.5 times as much. Iowa’s county land could hold about 134 areas the size of Des Moines County.
Another way to picture it: the same land area would fill a square about 20.4 miles (32.8 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 Des Moines County?
Des Moines County has more land than 793 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 Des Moines County at #2,447 nationally by total area, 18 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 3.2%, compared with a national county-equivalent median of 1.2% — 2 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 Des Moines County in the national ranking. They can be in different states and are not necessarily geographic neighbors.
| Land rank | County equivalent | Land mi² | Comparison |
|---|---|---|---|
| #2428 | Charlevoix County, Michigan | 416.3 | Compare |
| #2429 | Des Moines County, Iowa | 416.1 | This county |
| #2430 | Henry County, Ohio | 416 | 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 40.915339, -91.186925. 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: 1,077,769,214 m²; AWATER: 35,341,938 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 Des Moines County?
Des Moines County, Iowa has 416.1 square miles (1,077.8 km²) of land and 13.6 square miles of water, for a total area of 429.8 square miles. It ranks #2429 of 3,222 U.S. county equivalents by land area.
Is Des Moines County the largest county in Iowa?
No. Des Moines County ranks #93 of 99 in Iowa by land area. The largest is Kossuth County, with 972.7 square miles of land.
What counties border Des Moines County?
Des Moines County shares a land border with Henderson County, Illinois, Louisa County, Henry County, Lee County, and Mercer County, Illinois.
What is the population of Des Moines County?
The Census Bureau estimates Des Moines County had 38,077 residents on July 1, 2025, ranking #1,261 of 3,222 county equivalents. That is 92 people per square mile of land.
What is the county seat of Des Moines County?
The county seat of Des Moines County is Burlington.
What cities and towns are in Des Moines County?
Des Moines County has 5 incorporated places. The most populous are Burlington city, West Burlington city, Mediapolis city, Danville city, and Middletown city; 8,466 residents live outside any incorporated place.
Is Des Moines County part of a metropolitan area?
Yes. It is a central county of the Burlington, IA-IL Micropolitan Statistical Area, which has 2 county equivalents and 44,061 residents.
How many ZIP codes are in Des Moines County?
12 ZIP Code Tabulation Areas have land in Des Moines County, and 8 of them have most of their land inside the county. Census ZIP Code Tabulation Areas approximate USPS ZIP Code areas.
How does Des Moines County compare with U.S. states?
It has less land than every state. Rhode Island, the smallest, has 2.5 times as much land.
How many acres of land are in Des Moines County?
The land measurement converts to approximately 266,323 acres. Including water, total area is approximately 275,056 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.