County outline
Where Fond du Lac County is located
Area breakdown
Land accounts for 94% of Fond du Lac County’s measured area and water for 6%. Its combined area converts to 1,983.5 square kilometers or approximately 490,139 acres.
Green: land · blue: water
| Measurement | Square miles | Square kilometers | Acres |
|---|---|---|---|
| Land | 719.566 | 1,863.667 | 460,522.2 |
| Water | 46.276 | 119.854 | 29,616.6 |
| Total | 765.842 | 1,983.522 | 490,138.9 |
How Fond du Lac County compares
By original Census land area, Fond du Lac County ranks #40 of 72 in Wisconsin and #1247 of 3,222 nationally. National rankings include the 50 states, District of Columbia, and Puerto Rico.
Its land area is 0.956 times the Wisconsin county-equivalent median of 753 square miles. It accounts for 1.3% of the combined county land area in the state.
See the complete Wisconsin ranking · What counts as a county equivalent?
Population and density of Fond du Lac County
The Census Bureau estimates that 104,669 people lived in Fond du Lac County on July 1, 2025. That ranks #607 of 3,222 county equivalents nationally and #16 of 72 in Wisconsin. Since the April 1, 2020 estimates base of 104,165, the population has grown by 504 (+0.5%), compared with +1.3% for Wisconsin as a whole.
With 719.6 square miles of land, that is 145 people per square mile (56 per km²), placing Fond du Lac County #792 nationally for density and #18 in Wisconsin. The median county equivalent has 47 people per square mile; the Wisconsin median is 51. Put another way, there are about 4.4 acres of land per resident.
| July 1 | 2020 | 2021 | 2022 | 2023 | 2024 | 2025 |
|---|---|---|---|---|---|---|
| Estimate | 104,159 | 104,128 | 104,103 | 104,349 | 104,721 | 104,669 |
| Change | — | −31 | −25 | +246 | +372 | −52 |
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 Fond du Lac County
Fond du Lac County is divided into 34 cities and towns. In Wisconsin, county subdivisions are local governments, and together they cover all of the county’s land and residents.
The most populous is Fond du Lac city, with 44,541 residents (42.6% of the county). The largest by land is Byron town, at 36.4 mi², or 5.1% of the county’s land. Among those with at least 1,000 residents in 2020, Campbellsport village grew fastest since then (+6.7%).
| County subdivision | Population 2025 | Since 2020 | Land mi² | Share of county land |
|---|---|---|---|---|
| Fond du Lac cityCounty seat | 44,541 | −0.4% | 19.3 | 2.7% |
| Ripon city | 7,738 | −1.6% | 5.048 | 0.7% |
| North Fond du Lac village | 5,425 | +1.4% | 2.217 | 0.3% |
| Taycheedah town | 4,690 | +3% | 30 | 4.2% |
| Fond du Lac townCounty seat | 3,780 | +3.4% | 17.5 | 2.4% |
| Waupun city | 3,557 | +0.4% | 2.192 | 0.3% |
| Empire town | 2,790 | +0.6% | 28.6 | 4% |
| Friendship town | 2,774 | +0.8% | 16.5 | 2.3% |
| Auburn town | 2,404 | +1.8% | 34.9 | 4.9% |
| Campbellsport village | 2,034 | +6.7% | 1.366 | 0.2% |
| Osceola town | 1,874 | +1.8% | 34.8 | 4.8% |
| Lamartine town | 1,781 | +2.2% | 36.3 | 5% |
| Ashford town | 1,746 | +1.7% | 35.4 | 4.9% |
| Byron town | 1,679 | +0.4% | 36.4 | 5.1% |
| Calumet town | 1,432 | +1.3% | 30.1 | 4.2% |
Show the other 19 subdivisions
| Name | Population 2025 | Since 2020 | Land mi² |
|---|---|---|---|
| Eldorado town | 1,399 | −0.1% | 35.7 |
| Waupun town | 1,390 | +1.3% | 34 |
| Ripon town | 1,320 | +0.6% | 30.7 |
| Marshfield town | 1,199 | +0.6% | 33.9 |
| Oakfield village | 1,065 | +1.1% | 0.983 |
| Eden town | 1,062 | +5.5% | 35.8 |
| Alto town | 1,046 | −0.7% | 36 |
| Rosendale village | 1,042 | −0.5% | 1.248 |
| Forest town | 971 | +0.4% | 35.6 |
| Eden village | 917 | +3.3% | 0.598 |
| Brandon village | 875 | −0.8% | 0.758 |
| Rosendale town | 743 | +1.1% | 35.1 |
| Metomen town | 689 | −0.3% | 34.6 |
| Oakfield town | 689 | +1.2% | 35.5 |
| Springvale town | 683 | +0.9% | 35.8 |
| Mount Calvary village | 492 | +0.4% | 1.056 |
| St. Cloud village | 491 | +0.4% | 0.92 |
| Fairwater village | 351 | +0.3% | 0.735 |
| Kewaskum village | 0 | — | 0.063 |
Population: U.S. Census Bureau Vintage 2025 subcounty estimates, counting only the part of each subdivision inside Fond du Lac County. Land: 2026 Census Gazetteer. How communities are listed.
Metropolitan area
Fond du Lac County is a central county of the Fond du Lac, WI Metropolitan Statistical Area. Fond du Lac County is the area’s only county equivalent, so the metro area has the same 719.6 square miles of land. By combined land it ranks #316 of 393 metropolitan areas, and #360 by population.
ZIP codes
24 ZIP Code Tabulation Areas have land in Fond du Lac County; 15 of them have most of their land inside the county, and the others mainly cover neighboring areas.
530065301053011530145301953040530485304953057530615306553079539195393153946539635490454932549355493754964549715497454979
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 Fond du Lac County
Fond du Lac County shares a land border with 6 county equivalents. It has more land than 5 of them. The largest neighbor is Dodge County (875.7 mi²) and the smallest is Calumet County (318.3 mi²). Together with its neighbors, Fond du Lac County forms a block of 3,639.9 mi² of land, of which it holds 19.8%.
| Bordering county equivalent | Land mi² | Size vs. Fond du Lac | Compare |
|---|---|---|---|
| Dodge County | 875.7 | 1.2× larger | Compare |
| Sheboygan County | 511.5 | 1.4× smaller | Compare |
| Winnebago County | 434.7 | 1.7× smaller | Compare |
| Washington County | 430.6 | 1.7× smaller | Compare |
| Green Lake County | 349.5 | 2.1× smaller | Compare |
| Calumet County | 318.3 | 2.3× smaller | Compare |
How big is Fond du Lac County compared with U.S. states?
Fond du Lac County has less land than any of the 50 states. Rhode Island, the smallest state by land area, has 1,033.9 mi², about 1.4 times as much. Wisconsin’s county land could hold about 75 areas the size of Fond du Lac County.
Another way to picture it: the same land area would fill a square about 26.8 miles (43.2 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 Fond du Lac County?
Fond du Lac County has more land than 1,975 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 Fond du Lac County at #1,252 nationally by total area, 5 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 6%, compared with a national county-equivalent median of 1.2% — 4.9 percentage points higher. 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 Fond du Lac County in the national ranking. They can be in different states and are not necessarily geographic neighbors.
| Land rank | County equivalent | Land mi² | Comparison |
|---|---|---|---|
| #1246 | Perry County, Alabama | 719.7 | Compare |
| #1247 | Fond du Lac County, Wisconsin | 719.6 | This county |
| #1248 | Lincoln County, Kansas | 719.4 | 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 43.754722, -88.493284. 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: 1,863,667,255 m²; AWATER: 119,853,824 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 Fond du Lac County?
Fond du Lac County, Wisconsin has 719.6 square miles (1,863.7 km²) of land and 46.3 square miles of water, for a total area of 765.8 square miles. It ranks #1247 of 3,222 U.S. county equivalents by land area.
Is Fond du Lac County the largest county in Wisconsin?
No. Fond du Lac County ranks #40 of 72 in Wisconsin by land area. The largest is Marathon County, with 1,545.2 square miles of land.
What counties border Fond du Lac County?
Fond du Lac County shares a land border with Dodge County, Winnebago County, Sheboygan County, Green Lake County, Calumet County, and Washington County.
What is the population of Fond du Lac County?
The Census Bureau estimates Fond du Lac County had 104,669 residents on July 1, 2025, ranking #607 of 3,222 county equivalents. That is 145 people per square mile of land.
What is the county seat of Fond du Lac County?
The county seat of Fond du Lac County is Fond du Lac.
What cities and towns are in Fond du Lac County?
Fond du Lac County has 34 county subdivisions (cities, towns and townships). The most populous five are Fond du Lac city, Ripon city, North Fond du Lac village, Taycheedah town, and Fond du Lac town.
Is Fond du Lac County part of a metropolitan area?
Yes. It is a central county of the Fond du Lac, WI Metropolitan Statistical Area.
How many ZIP codes are in Fond du Lac County?
24 ZIP Code Tabulation Areas have land in Fond du Lac County, and 15 of them have most of their land inside the county. Census ZIP Code Tabulation Areas approximate USPS ZIP Code areas.
How does Fond du Lac County compare with U.S. states?
It has less land than every state. Rhode Island, the smallest, has 1.4 times as much land.
How many acres of land are in Fond du Lac County?
The land measurement converts to approximately 460,522 acres. Including water, total area is approximately 490,139 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.