Hillsdale County area

Hillsdale County, Michigan covers 607 square miles: 598.2 square miles of land and 8.842 square miles of water. Its county seat is Hillsdale. An estimated 45,738 people lived there in 2025.

Official Census measurements · GEOID 260592026 Gazetteer · retrieved September 27, 2026
Land area598.2 mi²
Water area8.842 mi²
Population (2025)45,738
People per mi²76

County outline

Generalized outline of Hillsdale County, Michigan
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 Hillsdale County is located

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

Area breakdown

Land accounts for 98.5% of Hillsdale County’s measured area and water for 1.5%. Its combined area converts to 1,572.1 square kilometers or approximately 388,486 acres.

Green: land · blue: water

MeasurementSquare milesSquare kilometersAcres
Land598.1671,549.245382,826.9
Water8.84222.9015,658.9
Total607.0091,572.146388,485.8

How Hillsdale County compares

By original Census land area, Hillsdale County ranks #36 of 83 in Michigan and #1629 of 3,222 nationally. National rankings include the 50 states, District of Columbia, and Puerto Rico.

Its land area is 1.053 times the Michigan county-equivalent median of 567.8 square miles. It accounts for 1.1% of the combined county land area in the state.

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

Population and density of Hillsdale County

The Census Bureau estimates that 45,738 people lived in Hillsdale County on July 1, 2025. That ranks #1,098 of 3,222 county equivalents nationally and #38 of 83 in Michigan. Since the April 1, 2020 estimates base of 45,757, the population has declined by 19 (−0%), compared with +0.5% for Michigan as a whole.

With 598.2 square miles of land, that is 76 people per square mile (30 per km²), placing Hillsdale County #1,192 nationally for density and #35 in Michigan. The median county equivalent has 47 people per square mile; the Michigan median is 62. Put another way, there are about 8.4 acres of land per resident.

Estimated population, 2020–2025 · line scaled to this county’s own range
July 1202020212022202320242025
Estimate45,74045,64745,73245,64345,69445,738
Change—−93+85−89+51+44

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 Hillsdale County

Hillsdale 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 Hillsdale city, with 8,002 residents (17.5% of the county). The largest by land is Wright township, at 43.3 mi², or 7.2% of the county’s land. Among those with at least 1,000 residents in 2020, Scipio township grew fastest since then (+0.9%).

County subdivisionPopulation 2025Since 2020Land mi²Share of county land
Hillsdale cityCounty seat8,002−0.4%5.7081%
Somerset township4,606+0.3%33.45.6%
Jefferson township3,037+0.7%35.55.9%
Cambria township2,5470%34.85.8%
Adams township2,3300%35.66%
Jonesville city2,175−0.3%2.7930.5%
Camden township2,075+0%42.47.1%
Hillsdale townshipCounty seat2,000−0.1%12.62.1%
Scipio township1,855+0.9%29.24.9%
Reading township1,734+0.2%345.7%
Allen township1,612+0.8%366%
Wright township1,600−0.9%43.37.2%
Pittsford township1,536−0.1%35.45.9%
Litchfield city1,394−0.1%2.7760.5%
Moscow township1,380+0.4%35.15.9%
Show the other 7 subdivisions
NamePopulation 2025Since 2020Land mi²
Wheatland township1,342−0.1%35.7
Woodbridge township1,308−0.5%30.1
Amboy township1,176−0.3%30
Fayette township1,107−0.4%20
Reading city1,084−1%1.012
Litchfield township1,030−0.1%32.7
Ransom township808−0.6%30.1

Population: U.S. Census Bureau Vintage 2025 subcounty estimates, counting only the part of each subdivision inside Hillsdale County. Land: 2026 Census Gazetteer. How communities are listed.

Metropolitan area

Hillsdale County is a central county of the Hillsdale, MI Micropolitan Statistical Area. Hillsdale County is the area’s only county equivalent, so the micro area has the same 598.2 square miles of land. By combined land it ranks #353 of 542 micropolitan areas, and #264 by population.

ZIP codes

19 ZIP Code Tabulation Areas have land in Hillsdale County; 13 of them have most of their land inside the county, and the others mainly cover neighboring areas.

49082492204922749232492334924249246492474924949250492524925549258492624926649271492744928249288

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 Hillsdale County

Hillsdale County shares a land border with 7 county equivalents, including 3 in Ohio and Indiana. It has more land than 4 of them. The largest neighbor is Lenawee County (749.7 mi²) and the smallest is Steuben County (308.8 mi²). Together with its neighbors, Hillsdale County forms a block of 4,397.3 mi² of land, of which it holds 13.6%.

Map of Hillsdale County and the 7 county equivalents that border it Lenawee County, Michigan: 749.7 mi² landBranch County, Michigan: 506.4 mi² landWilliams County, Ohio: 420.7 mi² landJackson County, Michigan: 701.9 mi² landCalhoun County, Michigan: 706.3 mi² landSteuben County, Indiana: 308.8 mi² landFulton County, Ohio: 405.5 mi² land
Hillsdale 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. HillsdaleCompare
Lenawee County749.71.3× largerCompare
Calhoun County706.31.2× largerCompare
Jackson County701.91.2× largerCompare
Branch County506.41.2× smallerCompare
Williams CountyOhio420.71.4× smallerCompare
Fulton CountyOhio405.51.5× smallerCompare
Steuben CountyIndiana308.81.9× smallerCompare

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

Hillsdale County has less land than any of the 50 states. Rhode Island, the smallest state by land area, has 1,033.9 mi², about 1.7 times as much. Michigan’s county land could hold about 95 areas the size of Hillsdale County.

Land area: Hillsdale County and the closest-sized states
Hillsdale County598.2 mi²
Rhode Island1,033.9 mi²

Another way to picture it: the same land area would fill a square about 24.5 miles (39.4 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 Hillsdale County?

Hillsdale County has more land than 1,593 of the other 3,221 county equivalents in the dataset.

Land area compared with the typical county equivalent
Hillsdale County598.2 mi²
Michigan median567.8 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 Hillsdale County at #1,719 nationally by total area, 90 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 1.5%, compared with a national county-equivalent median of 1.2% — 0.3 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 Hillsdale County in the national ranking. They can be in different states and are not necessarily geographic neighbors.

Land rankCounty equivalentLand mi²Comparison
#1628LaPorte County, Indiana598.3Compare
#1629Hillsdale County, Michigan598.2This county
#1630Southeastern Connecticut Planning Region, Connecticut598.1Compare

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 41.927461, -84.637479. 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: 1,549,244,320 m²; AWATER: 22,901,955 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 Hillsdale County?

Hillsdale County, Michigan has 598.2 square miles (1,549.2 km²) of land and 8.842 square miles of water, for a total area of 607 square miles. It ranks #1629 of 3,222 U.S. county equivalents by land area.

Is Hillsdale County the largest county in Michigan?

No. Hillsdale County ranks #36 of 83 in Michigan by land area. The largest is Marquette County, with 1,809.1 square miles of land.

What counties border Hillsdale County?

Hillsdale County shares a land border with Lenawee County, Branch County, Williams County, Ohio, Jackson County, Calhoun County, Steuben County, Indiana, and Fulton County, Ohio.

What is the population of Hillsdale County?

The Census Bureau estimates Hillsdale County had 45,738 residents on July 1, 2025, ranking #1,098 of 3,222 county equivalents. That is 76 people per square mile of land.

What is the county seat of Hillsdale County?

The county seat of Hillsdale County is Hillsdale.

What cities and towns are in Hillsdale County?

Hillsdale County has 22 county subdivisions (cities, towns and townships). The most populous five are Hillsdale city, Somerset township, Jefferson township, Cambria township, and Adams township.

Is Hillsdale County part of a metropolitan area?

Yes. It is a central county of the Hillsdale, MI Micropolitan Statistical Area.

How many ZIP codes are in Hillsdale County?

19 ZIP Code Tabulation Areas have land in Hillsdale County, and 13 of them have most of their land inside the county. Census ZIP Code Tabulation Areas approximate USPS ZIP Code areas.

How does Hillsdale County compare with U.S. states?

It has less land than every state. Rhode Island, the smallest, has 1.7 times as much land.

How many acres of land are in Hillsdale County?

The land measurement converts to approximately 382,827 acres. Including water, total area is approximately 388,486 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

Download the complete CSV or JSON dataset