County outline
Where Montgomery County is located
Area breakdown
Land accounts for 98.2% of Montgomery County’s measured area and water for 1.8%. Its combined area converts to 1,062.7 square kilometers or approximately 262,591 acres.
Green: land · blue: water
| Measurement | Square miles | Square kilometers | Acres |
|---|---|---|---|
| Land | 403.111 | 1,044.053 | 257,991 |
| Water | 7.187 | 18.614 | 4,599.7 |
| Total | 410.298 | 1,062.667 | 262,590.7 |
How Montgomery County compares
By original Census land area, Montgomery County ranks #49 of 62 in New York and #2510 of 3,222 nationally. National rankings include the 50 states, District of Columbia, and Puerto Rico.
Its land area is 0.617 times the New York county-equivalent median of 653.7 square miles. It accounts for 0.9% 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 Montgomery County
The Census Bureau estimates that 50,046 people lived in Montgomery County on July 1, 2025. That ranks #1,024 of 3,222 county equivalents nationally and #46 of 62 in New York. Since the April 1, 2020 estimates base of 49,534, the population has grown by 512 (+1%), compared with −1% for New York as a whole.
With 403.1 square miles of land, that is 124 people per square mile (48 per km²), placing Montgomery County #859 nationally for density and #29 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 5.2 acres of land per resident.
| July 1 | 2020 | 2021 | 2022 | 2023 | 2024 | 2025 |
|---|---|---|---|---|---|---|
| Estimate | 49,499 | 49,512 | 49,454 | 49,531 | 49,580 | 50,046 |
| Change | — | +13 | −58 | +77 | +49 | +466 |
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 Montgomery County
Montgomery County is divided into 11 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 Amsterdam city, with 18,093 residents (36.2% of the county). The largest by land is Minden town, at 51 mi², or 12.7% of the county’s land. Among those with at least 1,000 residents in 2020, Amsterdam town grew fastest since then (+7%).
| County subdivision | Population 2025 | Since 2020 | Land mi² | Share of county land |
|---|---|---|---|---|
| Amsterdam city | 18,093 | −0.7% | 5.873 | 1.5% |
| Amsterdam town | 5,954 | +7% | 29.6 | 7.4% |
| Minden town | 4,226 | +1.3% | 51 | 12.7% |
| Canajoharie town | 3,649 | −0.5% | 42.6 | 10.6% |
| Mohawk town | 3,545 | −0.7% | 34.7 | 8.6% |
| Palatine town | 3,227 | +1.4% | 41.1 | 10.2% |
| Florida town | 2,756 | +3.3% | 50.1 | 12.4% |
| Glen town | 2,649 | +4.6% | 38.6 | 9.6% |
| St. Johnsville town | 2,589 | −0.1% | 16.8 | 4.2% |
| Root town | 2,002 | −0.7% | 50.7 | 12.6% |
| Charleston town | 1,356 | −0.1% | 42 | 10.4% |
Population: U.S. Census Bureau Vintage 2025 subcounty estimates, counting only the part of each subdivision inside Montgomery County. Land: 2026 Census Gazetteer. How communities are listed.
Metropolitan area
Montgomery County is a central county of the Amsterdam, NY Micropolitan Statistical Area. Montgomery County is the area’s only county equivalent, so the micro area has the same 403.1 square miles of land. By combined land it ranks #487 of 542 micropolitan areas, and #222 by population. It belongs to the Albany-Schenectady, NY Combined Statistical Area.
ZIP codes
20 ZIP Code Tabulation Areas have land in Montgomery County; 11 of them have most of their land inside the county, and the others mainly cover neighboring areas.
1201012053120661206812069120701207212086120951213712160121661217713317133201333913410134281345213459
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 Montgomery County
Montgomery County shares a land border with 6 county equivalents. It has more land than 1 of them. The largest neighbor is Herkimer County (1,410.6 mi²) and the smallest is Schenectady County (204.7 mi²). Together with its neighbors, Montgomery County forms a block of 4,947.4 mi² of land, of which it holds 8.1%.
| Bordering county equivalent | Land mi² | Size vs. Montgomery | Compare |
|---|---|---|---|
| Herkimer County | 1,410.6 | 3.5× larger | Compare |
| Otsego County | 1,001.7 | 2.5× larger | Compare |
| Saratoga County | 810 | 2× larger | Compare |
| Schoharie County | 621.8 | 1.5× larger | Compare |
| Fulton County | 495.5 | 1.2× larger | Compare |
| Schenectady County | 204.7 | 2× smaller | Compare |
How big is Montgomery County compared with U.S. states?
Montgomery County has less land than any of the 50 states. Rhode Island, the smallest state by land area, has 1,033.9 mi², about 2.6 times as much. New York’s county land could hold about 117 areas the size of Montgomery County.
Another way to picture it: the same land area would fill a square about 20.1 miles (32.3 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 Montgomery County?
Montgomery County has more land than 712 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 Montgomery County at #2,545 nationally by total area, 35 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 1.8%, compared with a national county-equivalent median of 1.2% — 0.6 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 Montgomery County in the national ranking. They can be in different states and are not necessarily geographic neighbors.
| Land rank | County equivalent | Land mi² | Comparison |
|---|---|---|---|
| #2509 | West Feliciana Parish, Louisiana | 403.2 | Compare |
| #2510 | Montgomery County, New York | 403.1 | This county |
| #2511 | Allen County, Ohio | 402.5 | 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 42.887667, -74.430403. 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: 1,044,053,040 m²; AWATER: 18,613,121 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 Montgomery County?
Montgomery County, New York has 403.1 square miles (1,044.1 km²) of land and 7.187 square miles of water, for a total area of 410.3 square miles. It ranks #2510 of 3,222 U.S. county equivalents by land area.
Is Montgomery County the largest county in New York?
No. Montgomery County ranks #49 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 Montgomery County?
Montgomery County shares a land border with Fulton County, Schoharie County, Schenectady County, Herkimer County, Otsego County, and Saratoga County.
What is the population of Montgomery County?
The Census Bureau estimates Montgomery County had 50,046 residents on July 1, 2025, ranking #1,024 of 3,222 county equivalents. That is 124 people per square mile of land.
What is the county seat of Montgomery County?
The county seat of Montgomery County is Fonda.
What cities and towns are in Montgomery County?
Montgomery County has 11 county subdivisions (cities, towns and townships). The most populous five are Amsterdam city, Amsterdam town, Minden town, Canajoharie town, and Mohawk town.
Is Montgomery County part of a metropolitan area?
Yes. It is a central county of the Amsterdam, NY Micropolitan Statistical Area.
How many ZIP codes are in Montgomery County?
20 ZIP Code Tabulation Areas have land in Montgomery County, and 11 of them have most of their land inside the county. Census ZIP Code Tabulation Areas approximate USPS ZIP Code areas.
How does Montgomery County compare with U.S. states?
It has less land than every state. Rhode Island, the smallest, has 2.6 times as much land.
How many acres of land are in Montgomery County?
The land measurement converts to approximately 257,991 acres. Including water, total area is approximately 262,591 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.