County outline
Where Hamilton County is located
Area breakdown
Land accounts for 95% of Hamilton County’s measured area and water for 5%. Its combined area converts to 4,682.2 square kilometers or approximately 1,156,995 acres.
Green: land · blue: water
| Measurement | Square miles | Square kilometers | Acres |
|---|---|---|---|
| Land | 1,717.378 | 4,447.989 | 1,099,121.9 |
| Water | 90.427 | 234.205 | 57,873.3 |
| Total | 1,807.805 | 4,682.193 | 1,156,995.2 |
How Hamilton County compares
By original Census land area, Hamilton County ranks #3 of 62 in New York and #347 of 3,222 nationally. National rankings include the 50 states, District of Columbia, and Puerto Rico.
Its land area is 2.627 times the New York county-equivalent median of 653.7 square miles. It accounts for 3.6% 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 Hamilton County
The Census Bureau estimates that 5,006 people lived in Hamilton County on July 1, 2025. That ranks #2,892 of 3,222 county equivalents nationally and #62 of 62 in New York. Since the April 1, 2020 estimates base of 5,102, the population has declined by 96 (−1.9%), compared with −1% for New York as a whole.
With 1,717.4 square miles of land, that is 2.9 people per square mile (1.1 per km²), placing Hamilton County #2,990 nationally for density and #62 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 220 acres of land per resident.
| July 1 | 2020 | 2021 | 2022 | 2023 | 2024 | 2025 |
|---|---|---|---|---|---|---|
| Estimate | 5,073 | 5,109 | 5,102 | 5,068 | 5,083 | 5,006 |
| Change | — | +36 | −7 | −34 | +15 | −77 |
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 Hamilton County
Hamilton County is divided into 9 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 Indian Lake town, with 1,344 residents (26.8% of the county). The largest by land is Long Lake town, at 407 mi², or 23.7% of the county’s land. The county seat, Lake Pleasant town, has 886 residents.
| County subdivision | Population 2025 | Since 2020 | Land mi² | Share of county land |
|---|---|---|---|---|
| Indian Lake town | 1,344 | −1.6% | 251.8 | 14.7% |
| Lake Pleasant townCounty seat | 886 | −1% | 188 | 10.9% |
| Long Lake town | 777 | −1.3% | 407 | 23.7% |
| Wells town | 653 | −4.7% | 176.8 | 10.3% |
| Hope town | 406 | +0.7% | 40.7 | 2.4% |
| Inlet town | 352 | −0.8% | 62.2 | 3.6% |
| Arietta town | 286 | −3.4% | 317.2 | 18.5% |
| Benson town | 214 | −4% | 82.6 | 4.8% |
| Morehouse town | 88 | −4.3% | 191.1 | 11.1% |
Population: U.S. Census Bureau Vintage 2025 subcounty estimates, counting only the part of each subdivision inside Hamilton County. Land: 2026 Census Gazetteer. How communities are listed.
Metropolitan area
Hamilton 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
14 ZIP Code Tabulation Areas have land in Hamilton County; 13 of them have most of their land inside the county, and the others mainly cover neighboring areas.
1203212108121341213912164121901281212842128471286413331133531336013436
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 Hamilton County
Hamilton County shares a land border with 7 county equivalents. It has more land than 5 of them. The largest neighbor is St. Lawrence County (2,679.5 mi²) and the smallest is Fulton County (495.5 mi²). Together with its neighbors, Hamilton County forms a block of 11,403.6 mi² of land, of which it holds 15.1%.
| Bordering county equivalent | Land mi² | Size vs. Hamilton | Compare |
|---|---|---|---|
| St. Lawrence County | 2,679.5 | 1.6× larger | Compare |
| Essex County | 1,794.1 | about the same | Compare |
| Franklin County | 1,629.3 | 1.1× smaller | Compare |
| Herkimer County | 1,410.6 | 1.2× smaller | Compare |
| Warren County | 867.2 | 2× smaller | Compare |
| Saratoga County | 810 | 2.1× smaller | Compare |
| Fulton County | 495.5 | 3.5× smaller | Compare |
How big is Hamilton County compared with U.S. states?
Hamilton County has more land than 1 of the 50 states. It is about 1.7 times the land area of Rhode Island (1,033.9 mi²), while Delaware, the next larger state, has 1.1 times as much land (1,948.6 mi²). New York’s county land could hold about 27 areas the size of Hamilton County.
Another way to picture it: the same land area would fill a square about 41.4 miles (66.7 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 Hamilton County?
Hamilton County has more land than 2,875 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 Hamilton County at #366 nationally by total area, 19 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 5%, compared with a national county-equivalent median of 1.2% — 3.8 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 Hamilton County in the national ranking. They can be in different states and are not necessarily geographic neighbors.
| Land rank | County equivalent | Land mi² | Comparison |
|---|---|---|---|
| #346 | Granite County, Montana | 1,727.2 | Compare |
| #347 | Hamilton County, New York | 1,717.4 | This county |
| #348 | Wheeler County, Oregon | 1,716 | 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 43.657879, -74.502456. 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: 4,447,989,317 m²; AWATER: 234,204,424 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 Hamilton County?
Hamilton County, New York has 1,717.4 square miles (4,448 km²) of land and 90.4 square miles of water, for a total area of 1,807.8 square miles. It ranks #347 of 3,222 U.S. county equivalents by land area.
Is Hamilton County the largest county in New York?
No. Hamilton County ranks #3 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 Hamilton County?
Hamilton County shares a land border with Herkimer County, Essex County, Warren County, Fulton County, St. Lawrence County, Franklin County, and Saratoga County.
What is the population of Hamilton County?
The Census Bureau estimates Hamilton County had 5,006 residents on July 1, 2025, ranking #2,892 of 3,222 county equivalents. That is 2.9 people per square mile of land.
What is the county seat of Hamilton County?
The county seat of Hamilton County is Lake Pleasant.
What cities and towns are in Hamilton County?
Hamilton County has 9 county subdivisions (cities, towns and townships). The most populous five are Indian Lake town, Lake Pleasant town, Long Lake town, Wells town, and Hope town.
Is Hamilton County part of a metropolitan area?
No. Hamilton County is outside every metropolitan and micropolitan statistical area in the July 2023 OMB delineation.
How many ZIP codes are in Hamilton County?
14 ZIP Code Tabulation Areas have land in Hamilton 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 Hamilton County compare with U.S. states?
It has more land than 1 of the 50 states, including Rhode Island (1,033.9 square miles of land).
How many acres of land are in Hamilton County?
The land measurement converts to approximately 1,099,122 acres. Including water, total area is approximately 1,156,995 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.