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Single Family ResidenceResidential
$527,059
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 88How well the pricing models agreed with each other on this home. Higher means the estimate rests on stronger, more consistent data.· as of Jul 14, 2026

21 RICHMOND ST

ISLIP, NY 11751
0
Baths
0.19 ac
Lot SizeThe size of the land the home sits on, from county records.

Valuation

$527K
$464K low$590K high
Est. Owner EquityRoughly how much of the home's value the owner would keep after paying off known loans. It is our estimate minus the loans still owed.$527,059
Est. Lendable EquityThe part of the owner's equity a lender would typically let them borrow against — about 80% of their equity.$421,647

Tax & Assessment

Assessed ValueThe value the county assigns to this home to calculate property tax. It is often lower than what the home would sell for.$34,200 (2025)
Assessed LandThe share of the county's assessed value that comes from the land itself, not the buildings.$7,100
Assessed ImprovementsThe share of the county's assessed value that comes from the buildings and other structures on the land.$27,100
Assessor Market ValueThe county assessor's own opinion of market value. It is separate from our estimate and updates on the county's schedule.$481,690

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.0.19
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 · 0.8 mi
H
Islip High SchoolB+
High · Grades 9–12 · 1.0 mi
M
Islip Middle SchoolC+
Middle · Grades 7–8 · 1.2 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.$119,596
Average incomeThe average household income. It runs higher than the median when a few high earners pull it up.$137,796
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%

Ownership

OccupancyWhether the owner appears to live here or somewhere else. It is inferred from the mailing address on record.Owner occupied
Company ownedWhether the owner is a company or trust rather than a person.No

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 Richmond 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 91% of homes in Islip
  • Has a smaller lot than 75% 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
$465K$1.9M

This home is worth more than 9% 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$527,059
CheaperTypical $651,429Pricier

Pricier than 9% of homes nearby

Lot size0.19 ac
SmallerTypical 0.24 acBigger

Bigger than 29% of homes nearby

How 21 Richmond St ranks against every home in each area.
MeasureThis homeIslipIslip 11751Suffolk County
Estimated valuepricier than$527,0599% of homes9% of homes14% of homes
Lot sizebigger than0.19 ac26% of homes29% of homes25% of homes

About 21 Richmond St

How much is 21 Richmond St, Islip, NY worth?

The TopHap Estimate for 21 Richmond St, Islip, NY is $527,059 as of Jul 14, 2026. The likely range is $463,901 to $590,217. The estimate is modelled from recorded sales, assessments and the property's own characteristics — it is not an appraisal.

When did 21 Richmond St, Islip, NY last sell?

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

What schools serve 21 Richmond St, Islip, NY?

21 Richmond 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 21 Richmond St, Islip, NY compare to other homes in Islip 11751?

Among the 4,166 homes in Islip 11751, it is worth more than 9% of them ($527,059 against a typical $651,429) and its lot is bigger than 29% of them (0.19 ac against a typical 0.24 ac). Measured against all of Suffolk County, it is worth more than 14% of homes there. These shares are recounted nightly from the full county assessor record for each area, not from active listings.

Closest homes

More homes in Islip 11751

Assigned schools

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See this home in context

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