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Triplex (3 Units, Any Combination)Residential

21 WILLIAM ST

AMSTERDAM, NY 12010
5
Beds
4
Baths
3,806 ft²
Living AreaTotal finished area of the structures, from county records. Some counties include shared space like hallways or a building gym, so it may not match a listing.
0.14 ac
Lot SizeThe size of the land the home sits on, from county records.
1880
Year BuiltThe year the home was originally built, according to county records.
2
StoriesHow many floors the home has above ground.
2
ParkingThe number of parking spaces on the property, including the garage.

Tax & Assessment

Property TaxThe property tax billed for this tax year. It usually pays for schools, roads, and local services.$2,504 (2026)
Assessed ValueThe value the county assigns to this home to calculate property tax. It is often lower than what the home would sell for.$50,000 (2025)
Assessed LandThe share of the county's assessed value that comes from the land itself, not the buildings.$1,200
Assessed ImprovementsThe share of the county's assessed value that comes from the buildings and other structures on the land.$48,800
Previous AssessedThe county's assessed value from the year before, useful for seeing how the assessment changed.$50,000
Assessor Market ValueThe county assessor's own opinion of market value. It is separate from our estimate and updates on the county's schedule.$147,059

Property Facts

Property TypeThe broad category the county puts this property in, such as residential or commercial.Triplex (3 Units, Any Combination)
StyleThe architectural style of the home, such as ranch or colonial.Traditional/Old
CountyMONTGOMERY
Lot (acres)The size of the land the home sits on, from county records.0.14
HeatingThe type of heating system in the home.Forced Air With Air Conditioning
GarageWhether the property has a garage, and details like whether it is attached to the home.Garage, Detached
PoolWhether the property has a pool, and what kind, such as in-ground.No
FeaturesExtra features found in county records. Records are not complete everywhere, so a missing feature does not always mean the home lacks it.Porch · 341 ft²

Assigned SchoolsThe public schools this address is zoned for. Boundaries change, so confirm with the district before you count on it.

M
Wilbur H Lynch Literacy AcademyC-
Middle · Grades 6–8 · 0.5 mi
E
Raphael J Mcnulty Academy for Intern Studies and LiteracyD+
Elementary · Grades PK–5 · 0.7 mi
H
Amsterdam High SchoolD
High · Grades 9–12 · 1.8 mi

District: Amsterdam City School District

Neighborhood · ZIP 12010These are comparison scores, not percentages. 100 equals the national average, so 150 means about 50% above average.

CrimeLocal crime compared with the rest of the country, where 100 is average. It reflects things like population density, income, and how crime gets reported.97
Air pollutionOverall air pollution compared with the rest of the country, where 100 is average. Lower is cleaner.84
EarthquakeEarthquake risk and likely building damage compared with the rest of the country, where 100 is average. Scores can run far above 100.66

Index scale: 100 = US average (tick). Lower is better.

Homes occupiedThe share of homes here that someone lives in. The rest sit empty, including vacation and for-sale homes.87%
Bachelor's or higherThe share of adults 25 and older whose highest degree is a bachelor's degree.15%
Poverty rateThe share of people whose household income falls below the federal poverty line, which varies by family size.13%
UnemploymentThe share of men 16 and older who are out of work and actively looking. Only men are counted in this figure.1.3%
PopulationHow many people live in this area.30,758
DensityPeople per square mile. Higher numbers mean a more crowded, urban area.230 / mi²
Median incomeThe middle household income here — half of households earn more, half earn less.$63,310
Average incomeThe average household income. It runs higher than the median when a few high earners pull it up.$76,860
Average tempThe average temperature here across a full year.46°F
Annual precipHow much rain and melted snow falls here in a typical year.42 in
SunshineThe share of daylight hours that get direct sun in a typical year, counting cloud cover.52%

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Data by ATTOM. Valuations are automated estimates, not appraisals. Photos from Google Street View and may not depict the current property state.

How this home compares

21 William St measured against every home in its neighborhood, its ZIP code and its county, using county assessor records refreshed nightly. A home can stand out in one of those areas and look ordinary in another, because each one holds a different mix of homes.

  • Bigger than 97% of homes in Amsterdam 12010
  • Has a smaller lot than 80% of homes in Montgomery County
  • Older than 89% of homes in Amsterdam 12010

How it measures up in Amsterdam 12010

The dot is this home. The mark in the middle is the typical home in Amsterdam 12010.

Living area3,806 ft²
SmallerTypical 1,736 ft²Bigger

Bigger than 97% of homes nearby

Lot size0.14 ac
SmallerTypical 0.29 acBigger

Bigger than 28% of homes nearby

Year built1880
OlderTypical 1940Newer

Newer than 11% of homes nearby

How 21 William St ranks against every home in each area.
MeasureThis homeAmsterdam 12010Montgomery County
Living areabigger than3,806 ft²97% of homes97% of homes
Lot sizebigger than0.14 ac28% of homes20% of homes
Year builtnewer than188011% of homes16% of homes

About 21 William St

When did 21 William St, Amsterdam, NY last sell?

21 William St, Amsterdam, NY last sold on Jan 1, 1900, according to the county's recorded deed.

How big is 21 William St, Amsterdam, NY?

21 William St, Amsterdam, NY has 5 bedrooms, 4 bathrooms, 3,806 square feet of living space and a 0.14-acre lot.

When was 21 William St, Amsterdam, NY built?

21 William St, Amsterdam, NY was built in 1880, making it 146 years old. It is a traditional/old home. The building has 2 stories.

What schools serve 21 William St, Amsterdam, NY?

21 William St, Amsterdam, NY is assigned to Wilbur H Lynch Literacy Academy (middle), rated C-; Raphael J Mcnulty Academy for Intern Studies and Literacy (elementary), rated D+; Amsterdam High School (high), rated D. All sit in Amsterdam City School District. Attendance boundaries change — confirm with the district before relying on an assignment.

How does 21 William St, Amsterdam, NY compare to other homes in Amsterdam 12010?

Among the 9,294 homes in Amsterdam 12010, it is bigger than 97% of them (3,806 ft² against a typical 1,736 ft²), its lot is bigger than 28% of them (0.14 ac against a typical 0.29 ac) and it is newer than 11% of them (1880 against a typical 1940). These shares are recounted nightly from the full county assessor record for each area, not from active listings.

What are the property taxes on 21 William St, Amsterdam, NY?

The 2026 property tax bill for 21 William St, Amsterdam, NY was $2,504. The county assessed it at $50,000.

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Assigned schools

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