Chickasaw County area

Chickasaw County, Iowa covers 505.7 square miles: 504.3 square miles of land and 1.334 square miles of water. Its county seat is New Hampton. An estimated 11,663 people lived there in 2025.

Official Census measurements · GEOID 190372026 Gazetteer · retrieved September 27, 2026
Land area504.3 mi²
Water area1.334 mi²
Population (2025)11,663
People per mi²23

County outline

Generalized outline of Chickasaw 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 Chickasaw County is located

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

Area breakdown

Land accounts for 99.7% of Chickasaw County’s measured area and water for 0.3%. Its combined area converts to 1,309.6 square kilometers or approximately 323,621 acres.

Green: land · blue: water

MeasurementSquare milesSquare kilometersAcres
Land504.3241,306.193322,767.4
Water1.3343.455853.8
Total505.6581,309.648323,621.1

How Chickasaw County compares

By original Census land area, Chickasaw County ranks #69 of 99 in Iowa and #2060 of 3,222 nationally. National rankings include the 50 states, District of Columbia, and Puerto Rico.

Its land area is 0.885 times the Iowa county-equivalent median of 569.6 square miles. It accounts for 0.9% of the combined county land area in the state.

See the complete Iowa ranking · What counts as a county equivalent?

Population and density of Chickasaw County

The Census Bureau estimates that 11,663 people lived in Chickasaw County on July 1, 2025. That ranks #2,378 of 3,222 county equivalents nationally and #65 of 99 in Iowa. Since the April 1, 2020 estimates base of 12,018, the population has declined by 355 (−3%), compared with +1.5% for Iowa as a whole.

With 504.3 square miles of land, that is 23 people per square mile (8.9 per km²), placing Chickasaw County #2,203 nationally for density and #59 in Iowa. The median county equivalent has 47 people per square mile; the Iowa median is 26. Put another way, there are about 28 acres of land per resident.

Estimated population, 2020–2025 · line scaled to this county’s own range
July 1202020212022202320242025
Estimate11,99511,89611,76511,71311,72411,663
Change—−99−131−52+11−61

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 Chickasaw County

9 incorporated places lie at least partly in Chickasaw County. Together they are home to 6,884 people (59%); the other 4,779 (41%) live outside any incorporated place, in unincorporated communities and rural areas.

The largest is New Hampton city, with 3,420 residents in the county.

Incorporated placePopulation 2025Since 2020Land mi²
New Hampton cityCounty seat3,420−2.2%3.352
Nashua cityAlso in 1 other county1,503−3.2%2.922
Fredericksburg city979−1%0.909
Lawler city391−3.7%0.955
Ionia city220−3.9%0.564
Alta Vista city216−4.8%0.752
North Washington city103−3.7%0.203
Bassett city43−2.3%0.392
Protivin cityAlso in 1 other county90%0.442

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

Metropolitan area

Chickasaw 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

9 ZIP Code Tabulation Areas have land in Chickasaw County; 6 of them have most of their land inside the county, and the others mainly cover neighboring areas.

506035061650630506455065850659506745215452171

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 Chickasaw County

Chickasaw County shares a land border with 5 county equivalents. It has more land than 3 of them. The largest neighbor is Fayette County (730.8 mi²) and the smallest is Bremer County (435.5 mi²). Together with its neighbors, Chickasaw County forms a block of 3,334.3 mi² of land, of which it holds 15.1%.

Map of Chickasaw County and the 5 county equivalents that border it Bremer County, Iowa: 435.5 mi² landHoward County, Iowa: 473.2 mi² landFloyd County, Iowa: 500.6 mi² landFayette County, Iowa: 730.8 mi² landWinneshiek County, Iowa: 689.8 mi² land
Chickasaw 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. ChickasawCompare
Fayette County730.81.4× largerCompare
Winneshiek County689.81.4× largerCompare
Floyd County500.6about the sameCompare
Howard County473.21.1× smallerCompare
Bremer County435.51.2× smallerCompare

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

Chickasaw County has less land than any of the 50 states. Rhode Island, the smallest state by land area, has 1,033.9 mi², about 2.1 times as much. Iowa’s county land could hold about 111 areas the size of Chickasaw County.

Land area: Chickasaw County and the closest-sized states
Chickasaw County504.3 mi²
Rhode Island1,033.9 mi²

Another way to picture it: the same land area would fill a square about 22.5 miles (36.1 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 Chickasaw County?

Chickasaw County has more land than 1,162 of the other 3,221 county equivalents in the dataset.

Land area compared with the typical county equivalent
Chickasaw County504.3 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 Chickasaw County at #2,155 nationally by total area, 95 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 0.3%, compared with a national county-equivalent median of 1.2% — 0.9 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 Chickasaw County in the national ranking. They can be in different states and are not necessarily geographic neighbors.

Land rankCounty equivalentLand mi²Comparison
#2059Fairfield County, Ohio504.4Compare
#2060Chickasaw County, Iowa504.3This county
#2061Athens County, Ohio504.1Compare

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 43.059741, -92.317210. 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: 1,306,192,627 m²; AWATER: 3,455,447 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 Chickasaw County?

Chickasaw County, Iowa has 504.3 square miles (1,306.2 km²) of land and 1.334 square miles of water, for a total area of 505.7 square miles. It ranks #2060 of 3,222 U.S. county equivalents by land area.

Is Chickasaw County the largest county in Iowa?

No. Chickasaw County ranks #69 of 99 in Iowa by land area. The largest is Kossuth County, with 972.7 square miles of land.

What counties border Chickasaw County?

Chickasaw County shares a land border with Bremer County, Howard County, Floyd County, Fayette County, and Winneshiek County.

What is the population of Chickasaw County?

The Census Bureau estimates Chickasaw County had 11,663 residents on July 1, 2025, ranking #2,378 of 3,222 county equivalents. That is 23 people per square mile of land.

What is the county seat of Chickasaw County?

The county seat of Chickasaw County is New Hampton.

What cities and towns are in Chickasaw County?

Chickasaw County has 9 incorporated places. The most populous five are New Hampton city, Nashua city, Fredericksburg city, Lawler city, and Ionia city; 4,779 residents live outside any incorporated place.

Is Chickasaw County part of a metropolitan area?

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

How many ZIP codes are in Chickasaw County?

9 ZIP Code Tabulation Areas have land in Chickasaw County, and 6 of them have most of their land inside the county. Census ZIP Code Tabulation Areas approximate USPS ZIP Code areas.

How does Chickasaw County compare with U.S. states?

It has less land than every state. Rhode Island, the smallest, has 2.1 times as much land.

How many acres of land are in Chickasaw County?

The land measurement converts to approximately 322,767 acres. Including water, total area is approximately 323,621 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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