Shelby County area

Shelby County, Iowa covers 591.4 square miles: 590.8 square miles of land and 0.574 square miles of water. Its county seat is Harlan. An estimated 11,689 people lived there in 2025.

Official Census measurements · GEOID 191652026 Gazetteer · retrieved September 27, 2026
Land area590.8 mi²
Water area0.574 mi²
Population (2025)11,689
People per mi²20

County outline

Generalized outline of Shelby County, Iowa
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 Shelby County is located

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

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

MeasurementSquare milesSquare kilometersAcres
Land590.7761,530.103378,096.6
Water0.5741.487367.4
Total591.351,531.589378,464

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.

Estimated population, 2020–2025 · line scaled to this county’s own range
July 1202020212022202320242025
Estimate11,71811,76311,71711,78811,77811,689
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 placePopulation 2025Since 2020Land mi²
Harlan cityCounty seat4,859−0.6%4.42
Shelby cityAlso in 1 other county714−0.1%2.124
Elk Horn city619+3.2%0.733
Earling city387−2.3%0.628
Irwin city315−1.6%0.586
Defiance city242−2%0.373
Panama city231−1.3%0.291
Portsmouth city186−1.1%0.307
Westphalia city132+0.8%0.098
Tennant city81+3.8%0.718
Kirkman city56+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%.

Map of Shelby County and the 5 county equivalents that border it Audubon County, Iowa: 443 mi² landHarrison County, Iowa: 696.9 mi² landCrawford County, Iowa: 714.2 mi² landPottawattamie County, Iowa: 951.3 mi² landCass County, Iowa: 564.3 mi² land
Shelby 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. ShelbyCompare
Pottawattamie County951.31.6× largerCompare
Crawford County714.21.2× largerCompare
Harrison County696.91.2× largerCompare
Cass County564.3about the sameCompare
Audubon County4431.3× smallerCompare

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.

Land area: Shelby County and the closest-sized states
Shelby County590.8 mi²
Rhode Island1,033.9 mi²

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.

Land area compared with the typical county equivalent
Shelby County590.8 mi²
Iowa median569.6 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 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 rankCounty equivalentLand mi²Comparison
#1655Barton County, Missouri592Compare
#1656Shelby County, Iowa590.8This county
#1657Guthrie County, Iowa590.6Compare

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.

Download the official county source ZIP ↗ · Methodology

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.

Cite this county

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