Ida County area

Ida County, Iowa covers 432.1 square miles: 431.5 square miles of land and 0.537 square miles of water. Its county seat is Ida Grove. An estimated 6,777 people lived there in 2025.

Official Census measurements · GEOID 190932026 Gazetteer · retrieved September 27, 2026
Land area431.5 mi²
Water area0.537 mi²
Population (2025)6,777
People per mi²16

County outline

Generalized outline of Ida 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 Ida County is located

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

Area breakdown

Land accounts for 99.9% of Ida County’s measured area and water for 0.1%. Its combined area converts to 1,119 square kilometers or approximately 276,512 acres.

Green: land · blue: water

MeasurementSquare milesSquare kilometersAcres
Land431.5131,117.614276,168.3
Water0.5371.391343.7
Total432.051,119.004276,512

How Ida County compares

By original Census land area, Ida County ranks #87 of 99 in Iowa and #2353 of 3,222 nationally. National rankings include the 50 states, District of Columbia, and Puerto Rico.

Its land area is 0.758 times the Iowa county-equivalent median of 569.6 square miles. It accounts for 0.8% of the combined county land area in the state.

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

Population and density of Ida County

The Census Bureau estimates that 6,777 people lived in Ida County on July 1, 2025. That ranks #2,749 of 3,222 county equivalents nationally and #92 of 99 in Iowa. Since the April 1, 2020 estimates base of 7,003, the population has declined by 226 (−3.2%), compared with +1.5% for Iowa as a whole.

With 431.5 square miles of land, that is 16 people per square mile (6.1 per km²), placing Ida County #2,449 nationally for density and #85 in Iowa. The median county equivalent has 47 people per square mile; the Iowa median is 26. Put another way, there are about 41 acres of land per resident.

Estimated population, 2020–2025 · line scaled to this county’s own range
July 1202020212022202320242025
Estimate7,0196,9646,8806,8126,7676,777
Change—−55−84−68−45+10

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 Ida County

5 incorporated places lie at least partly in Ida County. Together they are home to 4,764 people (70.3%); the other 2,013 (29.7%) live outside any incorporated place, in unincorporated communities and rural areas.

The largest is Ida Grove city, with 1,986 residents in the county.

Incorporated placePopulation 2025Since 2020Land mi²
Ida Grove cityCounty seat1,986−3.8%2.196
Holstein city1,470−2.6%1.577
Battle Creek city678−2.9%0.572
Galva city415−4.6%0.754
Arthur city215−2.7%0.147

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

Metropolitan area

Ida 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

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

510065101651018510195102051025510535106151431514455144851461

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 Ida County

Ida County shares a land border with 4 county equivalents. Each of them has more land than Ida County. The largest neighbor is Woodbury County (872.9 mi²) and the smallest is Sac County (575 mi²). Together with its neighbors, Ida County forms a block of 3,170.5 mi² of land, of which it holds 13.6%.

Map of Ida County and the 4 county equivalents that border it Woodbury County, Iowa: 872.9 mi² landSac County, Iowa: 575 mi² landCherokee County, Iowa: 576.9 mi² landCrawford County, Iowa: 714.2 mi² land
Ida 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. IdaCompare
Woodbury County872.92× largerCompare
Crawford County714.21.7× largerCompare
Cherokee County576.91.3× largerCompare
Sac County5751.3× largerCompare

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

Ida County has less land than any of the 50 states. Rhode Island, the smallest state by land area, has 1,033.9 mi², about 2.4 times as much. Iowa’s county land could hold about 129 areas the size of Ida County.

Land area: Ida County and the closest-sized states
Ida County431.5 mi²
Rhode Island1,033.9 mi²

Another way to picture it: the same land area would fill a square about 20.8 miles (33.4 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 Ida County?

Ida County has more land than 869 of the other 3,221 county equivalents in the dataset.

Land area compared with the typical county equivalent
Ida County431.5 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 Ida County at #2,435 nationally by total area, 82 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 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 Ida County in the national ranking. They can be in different states and are not necessarily geographic neighbors.

Land rankCounty equivalentLand mi²Comparison
#2352Lunenburg County, Virginia431.7Compare
#2353Ida County, Iowa431.5This county
#2354McIntosh County, Georgia431.3Compare

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 42.391860, -95.507421. 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: 1,117,614,350 m²; AWATER: 1,391,967 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 Ida County?

Ida County, Iowa has 431.5 square miles (1,117.6 km²) of land and 0.537 square miles of water, for a total area of 432.1 square miles. It ranks #2353 of 3,222 U.S. county equivalents by land area.

Is Ida County the largest county in Iowa?

No. Ida County ranks #87 of 99 in Iowa by land area. The largest is Kossuth County, with 972.7 square miles of land.

What counties border Ida County?

Ida County shares a land border with Woodbury County, Sac County, Cherokee County, and Crawford County.

What is the population of Ida County?

The Census Bureau estimates Ida County had 6,777 residents on July 1, 2025, ranking #2,749 of 3,222 county equivalents. That is 16 people per square mile of land.

What is the county seat of Ida County?

The county seat of Ida County is Ida Grove.

What cities and towns are in Ida County?

Ida County has 5 incorporated places. The most populous are Ida Grove city, Holstein city, Battle Creek city, Galva city, and Arthur city; 2,013 residents live outside any incorporated place.

Is Ida County part of a metropolitan area?

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

How many ZIP codes are in Ida County?

12 ZIP Code Tabulation Areas have land in Ida 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 Ida County compare with U.S. states?

It has less land than every state. Rhode Island, the smallest, has 2.4 times as much land.

How many acres of land are in Ida County?

The land measurement converts to approximately 276,168 acres. Including water, total area is approximately 276,512 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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