County outline
Where Buena Vista County is located
Area breakdown
Land accounts for 99.1% of Buena Vista County’s measured area and water for 0.9%. Its combined area converts to 1,502.8 square kilometers or approximately 371,345 acres.
Green: land · blue: water
| Measurement | Square miles | Square kilometers | Acres |
|---|---|---|---|
| Land | 574.899 | 1,488.982 | 367,935.4 |
| Water | 5.327 | 13.797 | 3,409.3 |
| Total | 580.226 | 1,502.778 | 371,344.6 |
How Buena Vista County compares
By original Census land area, Buena Vista County ranks #39 of 99 in Iowa and #1731 of 3,222 nationally. National rankings include the 50 states, District of Columbia, and Puerto Rico.
Its land area is 1.009 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 Buena Vista County
The Census Bureau estimates that 20,449 people lived in Buena Vista County on July 1, 2025. That ranks #1,863 of 3,222 county equivalents nationally and #31 of 99 in Iowa. Since the April 1, 2020 estimates base of 20,820, the population has declined by 371 (−1.8%), compared with +1.5% for Iowa as a whole.
With 574.9 square miles of land, that is 36 people per square mile (14 per km²), placing Buena Vista County #1,861 nationally for density and #33 in Iowa. The median county equivalent has 47 people per square mile; the Iowa median is 26. Put another way, there are about 18 acres of land per resident.
| July 1 | 2020 | 2021 | 2022 | 2023 | 2024 | 2025 |
|---|---|---|---|---|---|---|
| Estimate | 20,800 | 20,794 | 20,644 | 20,678 | 20,655 | 20,449 |
| Change | — | −6 | −150 | +34 | −23 | −206 |
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 Buena Vista County
10 incorporated places lie at least partly in Buena Vista County. Together they are home to 16,955 people (82.9%); the other 3,494 (17.1%) live outside any incorporated place, in unincorporated communities and rural areas.
The largest is Storm Lake city, with 11,590 residents in the county. Among places with at least 1,000 residents in 2020, Storm Lake city grew fastest since then (+2.8%).
| Incorporated place | Population 2025 | Since 2020 | Land mi² |
|---|---|---|---|
| Storm Lake cityCounty seat | 11,590 | +2.8% | 5.427 |
| Alta city | 1,958 | −6.3% | 1.078 |
| Newell city | 814 | −9.9% | 1.263 |
| Sioux Rapids city | 694 | −7.2% | 0.82 |
| Lakeside city | 684 | −2.4% | 0.226 |
| Albert City city | 601 | −10.8% | 0.545 |
| Marathon city | 213 | −7.8% | 0.749 |
| Rembrandt city | 193 | −8.1% | 0.235 |
| Linn Grove city | 148 | −8.1% | 0.558 |
| Truesdale city | 60 | −7.7% | 0.146 |
Population: U.S. Census Bureau Vintage 2025 subcounty estimates, counting only the part of each place inside Buena Vista County. Land: 2026 Census Gazetteer, for the whole place even where it extends into other counties. How communities are listed.
Metropolitan area
Buena Vista County is a central county of the Storm Lake, IA Micropolitan Statistical Area. Buena Vista County is the area’s only county equivalent, so the micro area has the same 574.9 square miles of land. By combined land it ranks #369 of 542 micropolitan areas, and #512 by population.
ZIP codes
14 ZIP Code Tabulation Areas have land in Buena Vista County; 8 of them have most of their land inside the county, and the others mainly cover neighboring areas.
5051050554505655056850576505855058850592510025100551020510335104751366
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 Buena Vista County
Buena Vista County shares a land border with 4 county equivalents. It has more land than 1 of them. The largest neighbor is Pocahontas County (577.3 mi²) and the smallest is Clay County (567.2 mi²). Together with its neighbors, Buena Vista County forms a block of 2,871.3 mi² of land, of which it holds 20%.
| Bordering county equivalent | Land mi² | Size vs. Buena Vista | Compare |
|---|---|---|---|
| Pocahontas County | 577.3 | about the same | Compare |
| Cherokee County | 576.9 | about the same | Compare |
| Sac County | 575 | about the same | Compare |
| Clay County | 567.2 | about the same | Compare |
How big is Buena Vista County compared with U.S. states?
Buena Vista 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 97 areas the size of Buena Vista County.
Another way to picture it: the same land area would fill a square about 24 miles (38.6 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 Buena Vista County?
Buena Vista County has more land than 1,491 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 Buena Vista County at #1,830 nationally by total area, 99 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 0.9%, compared with a national county-equivalent median of 1.2% — 0.3 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 Buena Vista County in the national ranking. They can be in different states and are not necessarily geographic neighbors.
| Land rank | County equivalent | Land mi² | Comparison |
|---|---|---|---|
| #1730 | Webster County, Nebraska | 574.9 | Compare |
| #1731 | Buena Vista County, Iowa | 574.9 | This county |
| #1732 | Grant County, Kansas | 574.8 | 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 42.741522, -95.141432. 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: 1,488,981,882 m²; AWATER: 13,798,140 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 Buena Vista County?
Buena Vista County, Iowa has 574.9 square miles (1,489 km²) of land and 5.327 square miles of water, for a total area of 580.2 square miles. It ranks #1731 of 3,222 U.S. county equivalents by land area.
Is Buena Vista County the largest county in Iowa?
No. Buena Vista County ranks #39 of 99 in Iowa by land area. The largest is Kossuth County, with 972.7 square miles of land.
What counties border Buena Vista County?
Buena Vista County shares a land border with Cherokee County, Pocahontas County, Sac County, and Clay County.
What is the population of Buena Vista County?
The Census Bureau estimates Buena Vista County had 20,449 residents on July 1, 2025, ranking #1,863 of 3,222 county equivalents. That is 36 people per square mile of land.
What is the county seat of Buena Vista County?
The county seat of Buena Vista County is Storm Lake.
What cities and towns are in Buena Vista County?
Buena Vista County has 10 incorporated places. The most populous five are Storm Lake city, Alta city, Newell city, Sioux Rapids city, and Lakeside city; 3,494 residents live outside any incorporated place.
Is Buena Vista County part of a metropolitan area?
Yes. It is a central county of the Storm Lake, IA Micropolitan Statistical Area.
How many ZIP codes are in Buena Vista County?
14 ZIP Code Tabulation Areas have land in Buena Vista 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 Buena Vista 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 Buena Vista County?
The land measurement converts to approximately 367,935 acres. Including water, total area is approximately 371,345 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.