County outline
Where Floyd County is located
Area breakdown
Land accounts for 99.8% of Floyd County’s measured area and water for 0.2%. Its combined area converts to 1,298.5 square kilometers or approximately 320,865 acres.
Green: land · blue: water
| Measurement | Square miles | Square kilometers | Acres |
|---|---|---|---|
| Land | 500.571 | 1,296.473 | 320,365.4 |
| Water | 0.781 | 2.023 | 499.8 |
| Total | 501.352 | 1,298.496 | 320,865.3 |
How Floyd County compares
By original Census land area, Floyd County ranks #72 of 99 in Iowa and #2080 of 3,222 nationally. National rankings include the 50 states, District of Columbia, and Puerto Rico.
Its land area is 0.879 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 Floyd County
The Census Bureau estimates that 14,901 people lived in Floyd County on July 1, 2025. That ranks #2,170 of 3,222 county equivalents nationally and #50 of 99 in Iowa. Since the April 1, 2020 estimates base of 15,629, the population has declined by 728 (−4.7%), compared with +1.5% for Iowa as a whole.
With 500.6 square miles of land, that is 30 people per square mile (11 per km²), placing Floyd County #2,011 nationally for density and #42 in Iowa. The median county equivalent has 47 people per square mile; the Iowa median is 26. Put another way, there are about 21 acres of land per resident.
| July 1 | 2020 | 2021 | 2022 | 2023 | 2024 | 2025 |
|---|---|---|---|---|---|---|
| Estimate | 15,595 | 15,463 | 15,317 | 15,306 | 15,081 | 14,901 |
| Change | — | −132 | −146 | −11 | −225 | −180 |
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 Floyd County
9 incorporated places lie at least partly in Floyd County. Together they are home to 9,979 people (67%); the other 4,922 (33%) live outside any incorporated place, in unincorporated communities and rural areas.
The largest is Charles City city, with 7,013 residents in the county.
| Incorporated place | Population 2025 | Since 2020 | Land mi² |
|---|---|---|---|
| Charles City cityCounty seat | 7,013 | −5.2% | 6.131 |
| Nora Springs cityAlso in 1 other county | 1,311 | −3.8% | 2.216 |
| Rockford city | 715 | −6% | 0.623 |
| Rudd city | 336 | −6.1% | 1.088 |
| Floyd city | 294 | −5.2% | 0.552 |
| Marble Rock city | 255 | −5.2% | 0.832 |
| Colwell city | 53 | −5.4% | 0.165 |
| Nashua cityAlso in 1 other county | 2 | 0% | 2.922 |
| Greene cityAlso in 1 other county | 0 | — | 1.141 |
Population: U.S. Census Bureau Vintage 2025 subcounty estimates, counting only the part of each place inside Floyd County. Land: 2026 Census Gazetteer, for the whole place even where it extends into other counties. How communities are listed.
Metropolitan area
Floyd 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 Floyd County; 7 of them have most of their land inside the county, and the others mainly cover neighboring areas.
50433504355045850460504615046850471506165062050636506455065350658
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 Floyd County
Floyd County shares a land border with 4 county equivalents. It has more land than 1 of them. The largest neighbor is Butler County (580.1 mi²) and the smallest is Mitchell County (469.3 mi²). Together with its neighbors, Floyd County forms a block of 2,622.6 mi² of land, of which it holds 19.1%.
| Bordering county equivalent | Land mi² | Size vs. Floyd | Compare |
|---|---|---|---|
| Butler County | 580.1 | 1.2× larger | Compare |
| Cerro Gordo County | 568.3 | 1.1× larger | Compare |
| Chickasaw County | 504.3 | about the same | Compare |
| Mitchell County | 469.3 | 1.1× smaller | Compare |
How big is Floyd County compared with U.S. states?
Floyd 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 112 areas the size of Floyd County.
Another way to picture it: the same land area would fill a square about 22.4 miles (36 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 Floyd County?
Floyd County has more land than 1,142 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 Floyd County at #2,178 nationally by total area, 98 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 0.2%, 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 Floyd County in the national ranking. They can be in different states and are not necessarily geographic neighbors.
| Land rank | County equivalent | Land mi² | Comparison |
|---|---|---|---|
| #2079 | St. Joseph County, Michigan | 500.6 | Compare |
| #2080 | Floyd County, Iowa | 500.6 | This county |
| #2081 | Allen County, Kansas | 500.3 | 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 43.052741, -92.787367. 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: 1,296,471,917 m²; AWATER: 2,023,929 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 Floyd County?
Floyd County, Iowa has 500.6 square miles (1,296.5 km²) of land and 0.781 square miles of water, for a total area of 501.4 square miles. It ranks #2080 of 3,222 U.S. county equivalents by land area.
Is Floyd County the largest county in Iowa?
No. Floyd County ranks #72 of 99 in Iowa by land area. The largest is Kossuth County, with 972.7 square miles of land.
What counties border Floyd County?
Floyd County shares a land border with Butler County, Mitchell County, Cerro Gordo County, and Chickasaw County.
What is the population of Floyd County?
The Census Bureau estimates Floyd County had 14,901 residents on July 1, 2025, ranking #2,170 of 3,222 county equivalents. That is 30 people per square mile of land.
What is the county seat of Floyd County?
The county seat of Floyd County is Charles City.
What cities and towns are in Floyd County?
Floyd County has 9 incorporated places. The most populous five are Charles City city, Nora Springs city, Rockford city, Rudd city, and Floyd city; 4,922 residents live outside any incorporated place.
Is Floyd County part of a metropolitan area?
No. Floyd County is outside every metropolitan and micropolitan statistical area in the July 2023 OMB delineation.
How many ZIP codes are in Floyd County?
13 ZIP Code Tabulation Areas have land in Floyd County, and 7 of them have most of their land inside the county. Census ZIP Code Tabulation Areas approximate USPS ZIP Code areas.
How does Floyd 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 Floyd County?
The land measurement converts to approximately 320,365 acres. Including water, total area is approximately 320,865 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.