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15 William Ave, Islip, NY 11751 Property Records

Suffolk County and Islip Town property record for 15 William Ave, Islip, NY 11751

Property Summary

Property TypeSingle Family Home
Details2,026 sqft · built 1968
Lot Size0.12 acres (5,227 sqft)
Owner2 Individual Names on File
Last Sale$480,000 (Jul 2019)
Tax Bill$13,020 (2024)
Deeds & MortgagesJul 2019 Sale
Apr 2017 Sale & Mortgage
Flood ZoneZone X (minimal risk)
APN472889 320.-1-71

Property Details

APN / Parcel Number

Primary APN472889 320.-1-71
Alternative APNs
  • 0500-320.00-01.00-071.000
  • 288932000000010710000000
  • 472800655030
  • 566920

Interior

Building Area2,026 sqft Living Area
1st Floor Area1,136 sqft
Basement Area890 sqft

Exterior

Year BuiltBuilt 1968
Effective Year BuiltEffective 1968
Lot Area5,227 sqft (0.12 acres)
Lot Width50 ft Width

Location & Zoning

Account Number566920
Street Address15 WILLIAM AVE
CityISLIP
StateNY
Zip11751-2722
Property CategoryResidential
Property TypeResidential > Single Family > Home
Local Zoning CodeB
Legal DescriptionX2218735Y187519 T044H00000000
Legal SubdivisionCOLUMBUS PK AMD MAP 1
Legal Block0001
Legal Lot Number100
JurisdictionSUFFOLK NY
Township / Civil DivisionISLIP
Census Block Group1
Census Block1016
Census Tract147401

Owner

Source: Suffolk County and Islip Town records · APN 472889 320.-1-71

Assessment roll updated August 11, 2026 · Last verified August 2026

Owner names and exact recorded amounts shown locked on this page are available instantly with a free trial.

Owner of Record2 Individual Names on File
Mailing Address15 WILLIAM AVE, ISLIP, NY 11751-2722
OccupancyOwner Occupied
Owner TypeIndividual

Deeds, Mortgages & Sale History

DateDocument
Jul 02, 2019Deed, Transfer
Apr 06, 2017Grant Deed, Transfer
FEDERAL SVGS BK

Assessor's Deed Record

Deed Names2 Verified Names on Deed
Last SaleJul 02, 2019 · Amount on Record
Deed SaleJul 02, 2019 · Amount on Record
Prior SaleApr 06, 2017 · Amount on Record
Deed Book / Page13017 / 973
Record UpdatedSep 20, 2026

July 2019: Deed, Transfer

Document TypeDeed
JurisdictionSUFFOLK NY
Recording DateJul 02, 2019
Property Address15 WILLIAM AVE, ISLIP, NY 11751-2722
Document Number0130170973
Book / Page13017 / 973
Instrument DateJun 24, 2019
Transaction TypeTransfer
Record UpdatedAug 20, 2021

Transaction

AmountAmount Recorded
Tax$0.00
Amount AccuracyFull Amount Stated
Additional
  • Arm's Length

Transferred From (Grantor/Seller)

NameVerified Name

Transferred To (Grantee/Buyer)

NameVerified Name

April 2017: Grant Deed, Transfer

Document TypeGrant Deed
JurisdictionSUFFOLK NY
Recording DateApr 06, 2017
Property Address15 WILLIAM AVE, ISLIP, NY 11751-2722
Document Number0129070481
Book / Page012907 / 000481
Instrument DateMar 13, 2017
Transaction TypeTransfer
Record UpdatedFeb 08, 2018
Title CompanyASSURED ABSTRACT SERVICES, ASSURED ABSTRACT SVCS

Transaction

AmountAmount Recorded
DownpaymentDownpayment on File
Loan-to-Value (LTV)LTV on Record
Tax$1,600.00
Amount AccuracyConfirmed
Additional
  • Arm's Length

Transferred From (Grantor/Seller)

NameVerified Name

Transferred To (Grantee/Buyer)

NameVerified Name
RelationshipJoint Tenants with Right of Survivorship
Address707 PETER PAUL DR WEST ISLIP NY 117953517, WEST ISLIP, NY 11795-3517

Mortgage

Document Number228050856
DateApr 06, 2017
Book Page022805/000856
Lender
NameFEDERAL SVGS BK
TypeFederal Savings Bank
AddressCHICAGO, IL 60607
Agreement
AmountAmount Recorded
Term360 Months
DueApr 05, 2047

Tax Assessment & Valuation

Source: Suffolk County and Islip Town records · Assessment roll updated August 11, 2026 · Last verified August 2026

Property Jurisdictions

TypeName
StateNew York
CountySuffolk County
County SubdivisionIslip Town
Unified School DistrictIslip Union Free School District (KG - 12)

Tax Bill & Assessment History

Assessed value and assessed market value are set for property tax purposes, not market price estimates; both are a fraction of this property's market value.

YearTax BillAssessed ValueAssessed Market Value
2025$39,500 (-) Land $5,500 Building $34,000$556,338 (-) Land $77,465 Building $478,873
2024$13,020.00$556,338 (+2.54%) Land $77,465 Building $478,873
2023$39,500 Land $5,500 Building $34,000$542,582 Land $75,549 Building $467,033

Flood & Wildfire

Source: FEMA National Flood Hazard Layer as of September 18, 2026 · FEMA NFIP claims and policies as of September 2026 · USDA Forest Service Wildfire Risk to Communities as of 2024 · Last verified October 2026

Flood

FEMA Flood ZoneZone X
minimal risk
Flood Insurance RequirementNot required
lenders may require it
Nearby Flood Policies4 in force
Nearby Flood Claims25 (1979–2023)
Claims Outside the SFHA18 of 25
Most Recent ClaimJul 2023 · river or lake flooding
Claims by Event
  • Severe Storms And Flooding, Mar 2010 · 2 claims

Wildfire

Wildfire RiskNot rated
no burnable land within ember reach

Values are read at the parcel center point; flood claims are located to the census block group, not this parcel; lenders make the official flood determination.

Internet Providers

Source: FCC Broadband Data Collection as of December 31, 2025 · Last verified October 2026

ProviderMax Down / Up (Mbps)
Optimum Communications
Fiber · Cable		8,000 / 8,000
Verizon
Fiber · Fixed Wireless in parts of the area		2,300 / 2,300

Based on FCC filings for 329 locations within half a mile of this property.

Drinking Water

Source: EPA Safe Drinking Water Information System as of 2026 Q3 · EPA water system boundaries as of March 2026 · Last verified October 2026

Water SystemSUFFOLK COUNTY WATER AUTHORITY
serves 1,100,000 people
Water SourceGroundwater
Last State InspectionJan 2024
Lead1 ppb (2025–2027)
action level 15 ppb

Violations Reported to EPA

Water QualityAsbestos
resolved · Jul 2020
Treatment and ProcedureNone
last 10 years
Monitoring and ReportingNone
last 3 years

Results are for the whole water system as reported to EPA, not water tested at this address; lead at the tap also depends on the building's own pipes. The full violation and enforcement history is in the system's EPA record.

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