County outline
Where Eaton County is located
Area breakdown
Land accounts for 99.3% of Eaton County’s measured area and water for 0.7%. Its combined area converts to 1,500.7 square kilometers or approximately 370,838 acres.
Green: land · blue: water
| Measurement | Square miles | Square kilometers | Acres |
|---|---|---|---|
| Land | 575.21 | 1,489.787 | 368,134.4 |
| Water | 4.224 | 10.94 | 2,703.4 |
| Total | 579.434 | 1,500.727 | 370,837.8 |
How Eaton County compares
By original Census land area, Eaton County ranks #37 of 83 in Michigan and #1725 of 3,222 nationally. National rankings include the 50 states, District of Columbia, and Puerto Rico.
Its land area is 1.013 times the Michigan county-equivalent median of 567.8 square miles. It accounts for 1% of the combined county land area in the state.
See the complete Michigan ranking · What counts as a county equivalent?
Population and density of Eaton County
The Census Bureau estimates that 109,581 people lived in Eaton County on July 1, 2025. That ranks #586 of 3,222 county equivalents nationally and #19 of 83 in Michigan. Since the April 1, 2020 estimates base of 109,188, the population has grown by 393 (+0.4%), compared with +0.5% for Michigan as a whole.
With 575.2 square miles of land, that is 191 people per square mile (74 per km²), placing Eaton County #658 nationally for density and #19 in Michigan. The median county equivalent has 47 people per square mile; the Michigan median is 62. Put another way, there are about 3.4 acres of land per resident.
| July 1 | 2020 | 2021 | 2022 | 2023 | 2024 | 2025 |
|---|---|---|---|---|---|---|
| Estimate | 109,174 | 108,866 | 108,864 | 108,915 | 109,180 | 109,581 |
| Change | — | −308 | −2 | +51 | +265 | +401 |
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 Eaton County
Eaton County is divided into 22 municipalities and townships. In Michigan, county subdivisions are local governments, and together they cover all of the county’s land and residents.
The most populous is Delta charter township, with 33,175 residents (30.3% of the county). The largest by land is Kalamo township, at 36.6 mi², or 6.4% of the county’s land. The county seat, Charlotte city, has 9,305 residents. Among those with at least 1,000 residents in 2020, Potterville city grew fastest since then (+2.7%).
| County subdivision | Population 2025 | Since 2020 | Land mi² | Share of county land |
|---|---|---|---|---|
| Delta charter township | 33,175 | +0.1% | 32.4 | 5.6% |
| Charlotte cityCounty seat | 9,305 | +0.1% | 6.451 | 1.1% |
| Grand Ledge city | 7,853 | +0.7% | 3.708 | 0.6% |
| Windsor charter township | 7,197 | +1% | 34.4 | 6% |
| Eaton Rapids city | 5,218 | +0.1% | 3.631 | 0.6% |
| Lansing city | 5,113 | +2.1% | 3.078 | 0.5% |
| Eaton Rapids township | 4,012 | +0.7% | 34 | 5.9% |
| Eaton township | 4,009 | +0.3% | 32 | 5.6% |
| Oneida charter township | 3,966 | −0.3% | 32.1 | 5.6% |
| Hamlin township | 3,238 | +0.4% | 34.3 | 6% |
| Bellevue township | 3,218 | +0.5% | 36.4 | 6.3% |
| Potterville city | 3,135 | +2.7% | 1.746 | 0.3% |
| Carmel township | 2,851 | +0.5% | 34 | 5.9% |
| Benton township | 2,776 | +0.4% | 33.5 | 5.8% |
| Walton township | 2,201 | +0.9% | 35.2 | 6.1% |
Show the other 7 subdivisions
| Name | Population 2025 | Since 2020 | Land mi² |
|---|---|---|---|
| Sunfield township | 2,055 | +0.5% | 36.1 |
| Vermontville township | 1,961 | +0.6% | 36.1 |
| Kalamo township | 1,776 | +0.5% | 36.6 |
| Chester township | 1,770 | +0.1% | 36 |
| Roxand township | 1,755 | +0.1% | 36.4 |
| Olivet city | 1,525 | −6.4% | 1.02 |
| Brookfield township | 1,472 | +0.5% | 36.1 |
Population: U.S. Census Bureau Vintage 2025 subcounty estimates, counting only the part of each subdivision inside Eaton County. Land: 2026 Census Gazetteer. How communities are listed.
Metropolitan area
Eaton County is a central county of the Lansing-East Lansing, MI Metropolitan Statistical Area. Its 3 county equivalents have 479,722 residents on 1,698.6 square miles of land; Eaton County accounts for 33.9% of the land and 22.8% of the residents. By combined land it ranks #189 of 393 metropolitan areas, and #116 by population. It belongs to the Lansing-East Lansing-Owosso, MI Combined Statistical Area.
| County equivalent | Population 2025 | Land mi² |
|---|---|---|
| Ingham County | 289,709 | 556.1 |
| Eaton County | 109,581 | 575.2 |
| Clinton County | 80,432 | 567.3 |
ZIP codes
19 ZIP Code Tabulation Areas have land in Eaton County; 10 of them have most of their land inside the county, and the others mainly cover neighboring areas.
48813488214882748837488424884948861488764889048897489064891148917490214907349076490964926449284
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 Eaton County
Eaton County shares a land border with 6 county equivalents. It has more land than 4 of them. The largest neighbor is Calhoun County (706.3 mi²) and the smallest is Barry County (553.1 mi²). Together with its neighbors, Eaton County forms a block of 4,231.2 mi² of land, of which it holds 13.6%.
| Bordering county equivalent | Land mi² | Size vs. Eaton | Compare |
|---|---|---|---|
| Calhoun County | 706.3 | 1.2× larger | Compare |
| Jackson County | 701.9 | 1.2× larger | Compare |
| Ionia County | 571.3 | about the same | Compare |
| Clinton County | 567.3 | about the same | Compare |
| Ingham County | 556.1 | about the same | Compare |
| Barry County | 553.1 | about the same | Compare |
How big is Eaton County compared with U.S. states?
Eaton 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. Michigan’s county land could hold about 98 areas the size of Eaton 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 Eaton County?
Eaton County has more land than 1,497 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 Eaton County at #1,837 nationally by total area, 112 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 0.7%, compared with a national county-equivalent median of 1.2% — 0.4 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 Eaton County in the national ranking. They can be in different states and are not necessarily geographic neighbors.
| Land rank | County equivalent | Land mi² | Comparison |
|---|---|---|---|
| #1724 | Randolph County, Illinois | 575.4 | Compare |
| #1725 | Eaton County, Michigan | 575.2 | This county |
| #1726 | Wheeler County, Nebraska | 575.2 | 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 42.589530, -84.846450. 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: 1,489,785,872 m²; AWATER: 10,939,438 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 Eaton County?
Eaton County, Michigan has 575.2 square miles (1,489.8 km²) of land and 4.224 square miles of water, for a total area of 579.4 square miles. It ranks #1725 of 3,222 U.S. county equivalents by land area.
Is Eaton County the largest county in Michigan?
No. Eaton County ranks #37 of 83 in Michigan by land area. The largest is Marquette County, with 1,809.1 square miles of land.
What counties border Eaton County?
Eaton County shares a land border with Barry County, Ingham County, Calhoun County, Clinton County, Ionia County, and Jackson County.
What is the population of Eaton County?
The Census Bureau estimates Eaton County had 109,581 residents on July 1, 2025, ranking #586 of 3,222 county equivalents. That is 191 people per square mile of land.
What is the county seat of Eaton County?
The county seat of Eaton County is Charlotte.
What cities and towns are in Eaton County?
Eaton County has 22 county subdivisions (cities, towns and townships). The most populous five are Delta charter township, Charlotte city, Grand Ledge city, Windsor charter township, and Eaton Rapids city.
Is Eaton County part of a metropolitan area?
Yes. It is a central county of the Lansing-East Lansing, MI Metropolitan Statistical Area, which has 3 county equivalents and 479,722 residents.
How many ZIP codes are in Eaton County?
19 ZIP Code Tabulation Areas have land in Eaton County, and 10 of them have most of their land inside the county. Census ZIP Code Tabulation Areas approximate USPS ZIP Code areas.
How does Eaton 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 Eaton County?
The land measurement converts to approximately 368,134 acres. Including water, total area is approximately 370,838 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.