Hancock County area

Hancock County, Iowa covers 573 square miles: 571 square miles of land and 2.033 square miles of water. Its county seat is Garner. An estimated 10,528 people lived there in 2025.

Official Census measurements · GEOID 190812026 Gazetteer · retrieved September 27, 2026
Land area571 mi²
Water area2.033 mi²
Population (2025)10,528
People per mi²18

County outline

Generalized outline of Hancock 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 Hancock County is located

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

Area breakdown

Land accounts for 99.6% of Hancock County’s measured area and water for 0.4%. Its combined area converts to 1,484.2 square kilometers or approximately 366,744 acres.

Green: land · blue: water

MeasurementSquare milesSquare kilometersAcres
Land571.0051,478.896365,443.2
Water2.0335.2651,301.1
Total573.0381,484.162366,744.3

How Hancock County compares

By original Census land area, Hancock County ranks #45 of 99 in Iowa and #1763 of 3,222 nationally. National rankings include the 50 states, District of Columbia, and Puerto Rico.

Its land area is 1.003 times the Iowa county-equivalent median of 569.6 square miles. It accounts for 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 Hancock County

The Census Bureau estimates that 10,528 people lived in Hancock County on July 1, 2025. That ranks #2,448 of 3,222 county equivalents nationally and #69 of 99 in Iowa. Since the April 1, 2020 estimates base of 10,799, the population has declined by 271 (−2.5%), compared with +1.5% for Iowa as a whole.

With 571 square miles of land, that is 18 people per square mile (7.1 per km²), placing Hancock County #2,373 nationally for density and #75 in Iowa. The median county equivalent has 47 people per square mile; the Iowa median is 26. Put another way, there are about 35 acres of land per resident.

Estimated population, 2020–2025 · line scaled to this county’s own range
July 1202020212022202320242025
Estimate10,76310,69310,66210,63810,62010,528
Change—−70−31−24−18−92

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 Hancock County

9 incorporated places lie at least partly in Hancock County. Together they are home to 7,235 people (68.7%); the other 3,293 (31.3%) live outside any incorporated place, in unincorporated communities and rural areas.

The largest is Garner city, with 3,029 residents in the county. By land, Forest City city is the largest at 4.588 mi² across all its counties.

Incorporated placePopulation 2025Since 2020Land mi²
Garner cityCounty seat3,029−1.1%2.125
Britt city1,981−3.1%1.34
Kanawha city630−4%1.983
Klemme city424−3.9%0.5
Forest City cityAlso in 1 other county355−0.3%4.588
Corwith city253−4.5%1.448
Crystal Lake city240−5.9%0.248
Woden city185−4.1%0.493
Goodell city138−2.8%0.432

Population: U.S. Census Bureau Vintage 2025 subcounty estimates, counting only the part of each place inside Hancock County. Land: 2026 Census Gazetteer, for the whole place even where it extends into other counties. How communities are listed.

Metropolitan area

Hancock 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

13 ZIP Code Tabulation Areas have land in Hancock County; 8 of them have most of their land inside the county, and the others mainly cover neighboring areas.

50423504305043250436504385043950447504495045750480504825048350484

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 Hancock County

Hancock County shares a land border with 4 county equivalents. It has more land than 2 of them. The largest neighbor is Kossuth County (972.7 mi²) and the smallest is Winnebago County (400.5 mi²). Together with its neighbors, Hancock County forms a block of 3,092.9 mi² of land, of which it holds 18.5%.

Map of Hancock County and the 4 county equivalents that border it Cerro Gordo County, Iowa: 568.3 mi² landKossuth County, Iowa: 972.7 mi² landWinnebago County, Iowa: 400.5 mi² landWright County, Iowa: 580.4 mi² land
Hancock 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. HancockCompare
Kossuth County972.71.7× largerCompare
Wright County580.4about the sameCompare
Cerro Gordo County568.3about the sameCompare
Winnebago County400.51.4× smallerCompare

How big is Hancock County compared with U.S. states?

Hancock 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 98 areas the size of Hancock County.

Land area: Hancock County and the closest-sized states
Hancock County571 mi²
Rhode Island1,033.9 mi²

Another way to picture it: the same land area would fill a square about 23.9 miles (38.5 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 Hancock County?

Hancock County has more land than 1,459 of the other 3,221 county equivalents in the dataset.

Land area compared with the typical county equivalent
Hancock County571 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 Hancock County at #1,900 nationally by total area, 137 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 0.4%, compared with a national county-equivalent median of 1.2% — 0.8 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 Hancock County in the national ranking. They can be in different states and are not necessarily geographic neighbors.

Land rankCounty equivalentLand mi²Comparison
#1762Buchanan County, Iowa571.1Compare
#1763Hancock County, Iowa571This county
#1764Brown County, Kansas570.9Compare

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 43.075411, -93.743697. 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: 1,478,895,060 m²; AWATER: 5,265,568 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 Hancock County?

Hancock County, Iowa has 571 square miles (1,478.9 km²) of land and 2.033 square miles of water, for a total area of 573 square miles. It ranks #1763 of 3,222 U.S. county equivalents by land area.

Is Hancock County the largest county in Iowa?

No. Hancock County ranks #45 of 99 in Iowa by land area. The largest is Kossuth County, with 972.7 square miles of land.

What counties border Hancock County?

Hancock County shares a land border with Cerro Gordo County, Kossuth County, Winnebago County, and Wright County.

What is the population of Hancock County?

The Census Bureau estimates Hancock County had 10,528 residents on July 1, 2025, ranking #2,448 of 3,222 county equivalents. That is 18 people per square mile of land.

What is the county seat of Hancock County?

The county seat of Hancock County is Garner.

What cities and towns are in Hancock County?

Hancock County has 9 incorporated places. The most populous five are Garner city, Britt city, Kanawha city, Klemme city, and Forest City city; 3,293 residents live outside any incorporated place.

Is Hancock County part of a metropolitan area?

No. Hancock County is outside every metropolitan and micropolitan statistical area in the July 2023 OMB delineation.

How many ZIP codes are in Hancock County?

13 ZIP Code Tabulation Areas have land in Hancock 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 Hancock 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 Hancock County?

The land measurement converts to approximately 365,443 acres. Including water, total area is approximately 366,744 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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