County outline
Where Putnam County is located
Area breakdown
Land accounts for 93.5% of Putnam County’s measured area and water for 6.5%. Its combined area converts to 637.6 square kilometers or approximately 157,549 acres.
Green: land · blue: water
| Measurement | Square miles | Square kilometers | Acres |
|---|---|---|---|
| Land | 230.252 | 596.35 | 147,361.3 |
| Water | 15.919 | 41.23 | 10,188.2 |
| Total | 246.171 | 637.58 | 157,549.4 |
How Putnam County compares
By original Census land area, Putnam County ranks #55 of 62 in New York and #2950 of 3,222 nationally. National rankings include the 50 states, District of Columbia, and Puerto Rico.
Its land area is 0.352 times the New York county-equivalent median of 653.7 square miles. It accounts for 0.5% of the combined county land area in the state.
See the complete New York ranking · What counts as a county equivalent?
Population and density of Putnam County
The Census Bureau estimates that 99,028 people lived in Putnam County on July 1, 2025. That ranks #636 of 3,222 county equivalents nationally and #29 of 62 in New York. Since the April 1, 2020 estimates base of 97,680, the population has grown by 1,348 (+1.4%), compared with −1% for New York as a whole.
With 230.3 square miles of land, that is 430 people per square mile (166 per km²), placing Putnam County #387 nationally for density and #16 in New York. The median county equivalent has 47 people per square mile; the New York median is 112. Put another way, there are about 1.5 acres of land per resident.
| July 1 | 2020 | 2021 | 2022 | 2023 | 2024 | 2025 |
|---|---|---|---|---|---|---|
| Estimate | 97,636 | 98,272 | 98,361 | 98,110 | 98,842 | 99,028 |
| Change | — | +636 | +89 | −251 | +732 | +186 |
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 Putnam County
Putnam County is divided into 6 cities and towns. In New York, county subdivisions are local governments, and together they cover all of the county’s land and residents.
The most populous is Carmel town, with 34,442 residents (34.8% of the county). The largest by land is Philipstown town, at 48.8 mi², or 21.2% of the county’s land. Among those with at least 1,000 residents in 2020, Carmel town grew fastest since then (+2.5%).
| County subdivision | Population 2025 | Since 2020 | Land mi² | Share of county land |
|---|---|---|---|---|
| Carmel townCounty seat | 34,442 | +2.5% | 35.9 | 15.6% |
| Southeast town | 18,379 | +1.8% | 31.7 | 13.8% |
| Kent town | 12,895 | −0.1% | 40.5 | 17.6% |
| Putnam Valley town | 11,762 | +0.1% | 41.1 | 17.9% |
| Patterson town | 11,640 | +0.8% | 32.2 | 14% |
| Philipstown town | 9,910 | +0.8% | 48.8 | 21.2% |
Population: U.S. Census Bureau Vintage 2025 subcounty estimates, counting only the part of each subdivision inside Putnam County. Land: 2026 Census Gazetteer. How communities are listed.
Metropolitan area
Putnam County is a central county of the New York-Newark-Jersey City, NY-NJ Metropolitan Statistical Area, in the New York-Jersey City-White Plains, NY-NJ metropolitan division. Its 22 county equivalents have 20,112,448 residents on 6,139.7 square miles of land; Putnam County accounts for 3.8% of the land and 0.5% of the residents. By combined land it ranks #34 of 393 metropolitan areas, and #1 by population. It belongs to the New York-Newark, NY-NJ-CT-PA Combined Statistical Area.
| County equivalent | Population 2025 | Land mi² |
|---|---|---|
| Kings County | 2,653,963 | 69.4 |
| Queens County | 2,358,182 | 108.7 |
| New York County | 1,664,862 | 22.7 |
| Suffolk County | 1,546,090 | 910.9 |
| Bronx County | 1,406,332 | 42.2 |
| Nassau County | 1,398,939 | 284.5 |
| Westchester County | 1,015,743 | 430.8 |
| Bergen CountyNew Jersey | 977,026 | 232.8 |
| Essex CountyNew Jersey | 896,379 | 126.1 |
| Middlesex CountyNew Jersey | 883,335 | 309.3 |
| Hudson CountyNew Jersey | 735,033 | 46.2 |
| Ocean CountyNew Jersey | 673,746 | 628.3 |
| Monmouth CountyNew Jersey | 651,035 | 468.2 |
| Union CountyNew Jersey | 601,863 | 102.8 |
| Passaic CountyNew Jersey | 531,624 | 186.1 |
| Morris CountyNew Jersey | 524,251 | 461 |
| Richmond County | 501,290 | 57.5 |
| Rockland County | 357,397 | 173.7 |
| Somerset CountyNew Jersey | 356,486 | 301.9 |
| Sussex CountyNew Jersey | 148,063 | 518.5 |
| Hunterdon CountyNew Jersey | 131,781 | 427.8 |
| Putnam County | 99,028 | 230.3 |
ZIP codes
13 ZIP Code Tabulation Areas have land in Putnam County; 9 of them have most of their land inside the county, and the others mainly cover neighboring areas.
10509105121051610524105371054110542105791058812531125331256312582
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 Putnam County
Putnam County shares a land border with 5 county equivalents, including 1 in Connecticut. It has more land than 1 of them. The largest neighbor is Orange County (812.1 mi²) and the smallest is Rockland County (173.7 mi²). Together with its neighbors, Putnam County forms a block of 2,974.6 mi² of land, of which it holds 7.7%.
| Bordering county equivalent | Land mi² | Size vs. Putnam | Compare |
|---|---|---|---|
| Orange County | 812.1 | 3.5× larger | Compare |
| Dutchess County | 795.6 | 3.5× larger | Compare |
| Western Connecticut Planning RegionConnecticut | 532.1 | 2.3× larger | Compare |
| Westchester County | 430.8 | 1.9× larger | Compare |
| Rockland County | 173.7 | 1.3× smaller | Compare |
How big is Putnam County compared with U.S. states?
Putnam County has less land than any of the 50 states. Rhode Island, the smallest state by land area, has 1,033.9 mi², about 4.5 times as much. New York’s county land could hold about 205 areas the size of Putnam County.
Another way to picture it: the same land area would fill a square about 15.2 miles (24.4 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 Putnam County?
Putnam County has more land than 272 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 Putnam County at #2,962 nationally by total area, 12 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 6.5%, compared with a national county-equivalent median of 1.2% — 5.3 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 Putnam County in the national ranking. They can be in different states and are not necessarily geographic neighbors.
| Land rank | County equivalent | Land mi² | Comparison |
|---|---|---|---|
| #2949 | Pepin County, Wisconsin | 232 | Compare |
| #2950 | Putnam County, New York | 230.3 | This county |
| #2951 | Garrard County, Kentucky | 229.9 | 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 41.427907, -73.743861. 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: 596,350,750 m²; AWATER: 41,228,997 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 Putnam County?
Putnam County, New York has 230.3 square miles (596.3 km²) of land and 15.9 square miles of water, for a total area of 246.2 square miles. It ranks #2950 of 3,222 U.S. county equivalents by land area.
Is Putnam County the largest county in New York?
No. Putnam County ranks #55 of 62 in New York by land area. The largest is St. Lawrence County, with 2,679.5 square miles of land.
What counties border Putnam County?
Putnam County shares a land border with Dutchess County, Westchester County, Western Connecticut Planning Region, Connecticut, Orange County, and Rockland County.
What is the population of Putnam County?
The Census Bureau estimates Putnam County had 99,028 residents on July 1, 2025, ranking #636 of 3,222 county equivalents. That is 430 people per square mile of land.
What is the county seat of Putnam County?
The county seat of Putnam County is Carmel.
What cities and towns are in Putnam County?
Putnam County has 6 county subdivisions (cities, towns and townships). The most populous five are Carmel town, Southeast town, Kent town, Putnam Valley town, and Patterson town.
Is Putnam County part of a metropolitan area?
Yes. It is a central county of the New York-Newark-Jersey City, NY-NJ Metropolitan Statistical Area, which has 22 county equivalents and 20,112,448 residents.
How many ZIP codes are in Putnam County?
13 ZIP Code Tabulation Areas have land in Putnam County, and 9 of them have most of their land inside the county. Census ZIP Code Tabulation Areas approximate USPS ZIP Code areas.
How does Putnam County compare with U.S. states?
It has less land than every state. Rhode Island, the smallest, has 4.5 times as much land.
How many acres of land are in Putnam County?
The land measurement converts to approximately 147,361 acres. Including water, total area is approximately 157,549 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.