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Single Family ResidenceResidential
$532,479$432 / ft²
TopHap EstimateOur estimate of what this home would sell for today, based on nearby sales, the home's size and features, and local price trends. It is a starting point, not an appraisal.· confidence 94How well the pricing models agreed with each other on this home. Higher means the estimate rests on stronger, more consistent data.· as of Aug 30, 2026
Last sold for $322,500 on Aug 14, 2017

20 WALNUT ST

ISLIP, NY 11751
0
Baths
1,232 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.
1928
Year BuiltThe year the home was originally built, according to county records.

Valuation

$532K
$501K low$564K high
Last SaleThe most recent sale price and date from the recorded deed. Transfers between family members or companies may not reflect market value.$322,500 · Aug 14, 2017

Tax & Assessment

Property TaxThe property tax billed for this tax year. It usually pays for schools, roads, and local services.$9,221 (2024)
Assessed ValueThe value the county assigns to this home to calculate property tax. It is often lower than what the home would sell for.$27,500 (2025)
Assessed LandThe share of the county's assessed value that comes from the land itself, not the buildings.$5,500
Assessed ImprovementsThe share of the county's assessed value that comes from the buildings and other structures on the land.$22,000
Assessor Market ValueThe county assessor's own opinion of market value. It is separate from our estimate and updates on the county's schedule.$387,324

Climate Risk

Projected Flood DepthHow deep a serious flood is expected to get here at some point in the next 30 years. Shown in inches.2 in
30-Year Flood ChanceThe chance of at least one serious flood here in the next 30 years, not in any single year.30%
FEMA Flood ZoneFEMA's flood zone for this address. Zones starting with A or V are high risk, and lenders usually require flood insurance there.minimal

Scores 0–100; higher = greater projected risk.

Property Facts

Property TypeThe broad category the county puts this property in, such as residential or commercial.Single Family Residence
CountySUFFOLK
Lot (acres)The size of the land the home sits on, from county records.0.14
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

Transaction History(1)

Sales and refinances filed with the county for this home. Not every transfer is a normal sale, so check the type before comparing prices.

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

E
Wing Elementary School
Elementary · Grades KG–1 · 0.4 mi
H
Islip High SchoolB+
High · Grades 9–12 · 1.2 mi
M
Islip Middle SchoolC+
Middle · Grades 7–8 · 1.4 mi

District: Islip Union Free School District

Neighborhood · ZIP 11751These 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.59
Air pollutionOverall air pollution compared with the rest of the country, where 100 is average. Lower is cleaner.102
EarthquakeEarthquake risk and likely building damage compared with the rest of the country, where 100 is average. Scores can run far above 100.69

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.97%
Bachelor's or higherThe share of adults 25 and older whose highest degree is a bachelor's degree.19%
Poverty rateThe share of people whose household income falls below the federal poverty line, which varies by family size.4.2%
UnemploymentThe share of men 16 and older who are out of work and actively looking. Only men are counted in this figure.1.1%
PopulationHow many people live in this area.15,527
DensityPeople per square mile. Higher numbers mean a more crowded, urban area.3,057 / mi²
Median incomeThe middle household income here — half of households earn more, half earn less.$119,597
Average incomeThe average household income. It runs higher than the median when a few high earners pull it up.$137,797
Average tempThe average temperature here across a full year.52°F
Annual precipHow much rain and melted snow falls here in a typical year.48 in
SunshineThe share of daylight hours that get direct sun in a typical year, counting cloud cover.58%

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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

20 Walnut 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.

  • Worth less than 88% of homes in Islip 11751
  • Smaller than 78% of homes in Islip
  • Has a smaller lot than 95% of homes in Islip
  • Older than 96% of homes in Suffolk County

What homes are worth in Islip 11751

Each bar is how many homes fall in that price range. The marker is this home.

This home
$460K$1.8M

This home is worth more than 12% of homes in Islip 11751.

How it measures up in Islip 11751

The dot is this home. The mark in the middle is the typical home in Islip 11751.

Estimated value$532,479
CheaperTypical $646,679Pricier

Pricier than 12% of homes nearby

Price per ft²$432
CheaperTypical $434Pricier

Pricier than 49% of homes nearby

Living area1,232 ft²
SmallerTypical 1,654 ft²Bigger

Bigger than 24% of homes nearby

Lot size0.14 ac
SmallerTypical 0.24 acBigger

Bigger than 7% of homes nearby

Year built1928
OlderTypical 1957Newer

Newer than 20% of homes nearby

How 20 Walnut St ranks against every home in each area.
MeasureThis homeIslipIslip 11751Suffolk County
Estimated valuepricier than$532,47913% of homes12% of homes15% of homes
Price per ft²pricier than$43254% of homes49% of homes57% of homes
Living areabigger than1,232 ft²22% of homes24% of homes24% of homes
Lot sizebigger than0.14 ac5% of homes7% of homes13% of homes
Year builtnewer than192817% of homes20% of homes4% of homes

About 20 Walnut St

How much is 20 Walnut St, Islip, NY worth?

The TopHap Estimate for 20 Walnut St, Islip, NY is $532,479 as of Aug 30, 2026. The likely range is $500,652 to $564,306. The estimate is modelled from recorded sales, assessments and the property's own characteristics — it is not an appraisal.

When did 20 Walnut St, Islip, NY last sell?

20 Walnut St, Islip, NY last sold on Aug 14, 2017 for $322,500, according to the county's recorded deed.

How big is 20 Walnut St, Islip, NY?

20 Walnut St, Islip, NY has 1,232 square feet of living space and a 0.14-acre lot.

When was 20 Walnut St, Islip, NY built?

20 Walnut St, Islip, NY was built in 1928, making it 98 years old.

What schools serve 20 Walnut St, Islip, NY?

20 Walnut St, Islip, NY is assigned to Wing Elementary School (elementary); Islip High School (high), rated B+; Islip Middle School (middle), rated C+. All sit in Islip Union Free School District. Attendance boundaries change — confirm with the district before relying on an assignment.

How does 20 Walnut St, Islip, NY compare to other homes in Islip 11751?

Among the 4,166 homes in Islip 11751, it is worth more than 12% of them ($532,479 against a typical $646,679), its price per square foot is higher than 49% of them ($432 against a typical $434), it is bigger than 24% of them (1,232 ft² against a typical 1,654 ft²), its lot is bigger than 7% of them (0.14 ac against a typical 0.24 ac) and it is newer than 20% of them (1928 against a typical 1957). Measured against all of Suffolk County, it is worth more than 15% of homes there. These shares are recounted nightly from the full county assessor record for each area, not from active listings.

What are the property taxes on 20 Walnut St, Islip, NY?

The 2024 property tax bill for 20 Walnut St, Islip, NY was $9,221. The county assessed it at $27,500.

More homes on Walnut St

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Assigned schools

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