County outline
Where Shelby County is located
Area breakdown
Land accounts for 99.9% of Shelby County’s measured area and water for 0.1%. Its combined area converts to 1,531.6 square kilometers or approximately 378,464 acres.
Green: land · blue: water
| Measurement | Square miles | Square kilometers | Acres |
|---|---|---|---|
| Land | 590.776 | 1,530.103 | 378,096.6 |
| Water | 0.574 | 1.487 | 367.4 |
| Total | 591.35 | 1,531.589 | 378,464 |
How Shelby County compares
By original Census land area, Shelby County ranks #22 of 99 in Iowa and #1656 of 3,222 nationally. National rankings include the 50 states, District of Columbia, and Puerto Rico.
Its land area is 1.037 times the Iowa county-equivalent median of 569.6 square miles. It accounts for 1.1% of the combined county land area in the state.
See the complete Iowa ranking · What counts as a county equivalent?
Population and density of Shelby County
The Census Bureau estimates that 11,689 people lived in Shelby County on July 1, 2025. That ranks #2,376 of 3,222 county equivalents nationally and #64 of 99 in Iowa. Since the April 1, 2020 estimates base of 11,742, the population has declined by 53 (−0.5%), compared with +1.5% for Iowa as a whole.
With 590.8 square miles of land, that is 20 people per square mile (7.6 per km²), placing Shelby County #2,333 nationally for density and #73 in Iowa. The median county equivalent has 47 people per square mile; the Iowa median is 26. Put another way, there are about 32 acres of land per resident.
| July 1 | 2020 | 2021 | 2022 | 2023 | 2024 | 2025 |
|---|---|---|---|---|---|---|
| Estimate | 11,718 | 11,763 | 11,717 | 11,788 | 11,778 | 11,689 |
| Change | — | +45 | −46 | +71 | −10 | −89 |
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 Shelby County
11 incorporated places lie at least partly in Shelby County. Together they are home to 7,822 people (66.9%); the other 3,867 (33.1%) live outside any incorporated place, in unincorporated communities and rural areas.
The largest is Harlan city, with 4,859 residents in the county.
| Incorporated place | Population 2025 | Since 2020 | Land mi² |
|---|---|---|---|
| Harlan cityCounty seat | 4,859 | −0.6% | 4.42 |
| Shelby cityAlso in 1 other county | 714 | −0.1% | 2.124 |
| Elk Horn city | 619 | +3.2% | 0.733 |
| Earling city | 387 | −2.3% | 0.628 |
| Irwin city | 315 | −1.6% | 0.586 |
| Defiance city | 242 | −2% | 0.373 |
| Panama city | 231 | −1.3% | 0.291 |
| Portsmouth city | 186 | −1.1% | 0.307 |
| Westphalia city | 132 | +0.8% | 0.098 |
| Tennant city | 81 | +3.8% | 0.718 |
| Kirkman city | 56 | +1.8% | 0.257 |
Population: U.S. Census Bureau Vintage 2025 subcounty estimates, counting only the part of each place inside Shelby County. Land: 2026 Census Gazetteer, for the whole place even where it extends into other counties. How communities are listed.
Metropolitan area
Shelby 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
19 ZIP Code Tabulation Areas have land in Shelby County; 10 of them have most of their land inside the county, and the others mainly cover neighboring areas.
50022514465144751454514555152151527515295153051531515375154351552515625156351565515705157751578
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 Shelby County
Shelby County shares a land border with 5 county equivalents. It has more land than 2 of them. The largest neighbor is Pottawattamie County (951.3 mi²) and the smallest is Audubon County (443 mi²). Together with its neighbors, Shelby County forms a block of 3,960.4 mi² of land, of which it holds 14.9%.
| Bordering county equivalent | Land mi² | Size vs. Shelby | Compare |
|---|---|---|---|
| Pottawattamie County | 951.3 | 1.6× larger | Compare |
| Crawford County | 714.2 | 1.2× larger | Compare |
| Harrison County | 696.9 | 1.2× larger | Compare |
| Cass County | 564.3 | about the same | Compare |
| Audubon County | 443 | 1.3× smaller | Compare |
How big is Shelby County compared with U.S. states?
Shelby 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. Iowa’s county land could hold about 95 areas the size of Shelby County.
Another way to picture it: the same land area would fill a square about 24.3 miles (39.1 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 Shelby County?
Shelby County has more land than 1,566 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 Shelby County at #1,774 nationally by total area, 118 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 0.1%, compared with a national county-equivalent median of 1.2% — 1.1 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 Shelby County in the national ranking. They can be in different states and are not necessarily geographic neighbors.
| Land rank | County equivalent | Land mi² | Comparison |
|---|---|---|---|
| #1655 | Barton County, Missouri | 592 | Compare |
| #1656 | Shelby County, Iowa | 590.8 | This county |
| #1657 | Guthrie County, Iowa | 590.6 | 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 41.679014, -95.308917. 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: 1,530,103,547 m²; AWATER: 1,486,126 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 Shelby County?
Shelby County, Iowa has 590.8 square miles (1,530.1 km²) of land and 0.574 square miles of water, for a total area of 591.4 square miles. It ranks #1656 of 3,222 U.S. county equivalents by land area.
Is Shelby County the largest county in Iowa?
No. Shelby County ranks #22 of 99 in Iowa by land area. The largest is Kossuth County, with 972.7 square miles of land.
What counties border Shelby County?
Shelby County shares a land border with Audubon County, Harrison County, Crawford County, Pottawattamie County, and Cass County.
What is the population of Shelby County?
The Census Bureau estimates Shelby County had 11,689 residents on July 1, 2025, ranking #2,376 of 3,222 county equivalents. That is 20 people per square mile of land.
What is the county seat of Shelby County?
The county seat of Shelby County is Harlan.
What cities and towns are in Shelby County?
Shelby County has 11 incorporated places. The most populous five are Harlan city, Shelby city, Elk Horn city, Earling city, and Irwin city; 3,867 residents live outside any incorporated place.
Is Shelby County part of a metropolitan area?
No. Shelby County is outside every metropolitan and micropolitan statistical area in the July 2023 OMB delineation.
How many ZIP codes are in Shelby County?
19 ZIP Code Tabulation Areas have land in Shelby County, and 10 of them have most of their land inside the county. Census ZIP Code Tabulation Areas approximate USPS ZIP Code areas.
How does Shelby 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 Shelby County?
The land measurement converts to approximately 378,097 acres. Including water, total area is approximately 378,464 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.