| Primary address | 16 William Avenue, Islip |
| Zip code | 11751 |
| County | Suffolk |
| Municipality | Islip |
| Parcel ID | 319-3-83.10 |
View detailed information on past sales, title documents and property taxes, including the assessed market value, in their dedicated tabs.
| Sale date | 08/01/1997 |
| Sale price | $145,000 |
| Arm's length | Register |
| Current property tax | $11,210 |
| Building sqft | 2,479 |
| Building class | Two Family Year-Round Residence (220) |
| Acreage | 0.26 |
| Year built | 1996 |
| Units | 2 |
| Zoning district | Register |
| School district | Islip |
View more neighborhood information such as transportation, nearby schools and risk designations in the dedicated tab.
Property reports include comprehensive occupancy, improvement and development information (where available).
Create a free account to access valuable data points such as:
16 William Avenue, Islip, NY 11751 was built in 1996 and has a total of 2,479 square feet.
What is the assessed value of 16 William Avenue, Islip, NY 11751 and the property tax paid?Assessed at $51,000, the tax amount paid for 16 William Avenue, Islip, NY 11751 is $16,097.
When was 16 William Avenue, Islip, NY 11751 last sold?16 William Avenue, Islip, NY 11751 was last sold in 07/10/2023.
How many residential units does this building have?This building has 2 residential unit(s).
View detailed property contacts like owners, building management, representatives from permits and tenants with a free account.
Create a free account to view the complete sales history for 16 William Avenue, Islip, including title documents, transfer conditions, mortgages and liens.
| Purchase date | Purchase price | Buyer name | Seller name |
|---|---|---|---|
| 08/01/1997 | $145,000 | Register | Register |
To view the complete history of deeds, mortgages, assignments of leases and rents, and more, sign up for free. Available data goes back to 1966.
R: Recorded date
D: Document date
Access detailed property tax data for 16 William Avenue, Islip, NY 11751. Tax information included: property tax, market value and assessed value, exemptions, abatements, and assessment history.
| Tax year | 2025-2026 |
| Base tax | $16,098 |
| Current property tax | $11,210 |
| Market value | $718,310 |
| Assessed value | $51,000 |
Here's the assessment & property tax history for 16 William Avenue, Islip, including the evolution of the total tax rate and corresponding property tax.
| Year | Market value | Assessment value | Total tax rate | Property tax | Year over year change |
|---|---|---|---|---|---|
| 2025-2026 | $718,310 | $51,000 | 31.564 | $16,098 | +3.54% |
| 2024-2025 | $718,310 | $51,000 | 30.486 | $15,548 | +3.73% |
| 2023-2024 | $700,550 | $51,000 | 29.39 | $14,989 | +1.68% |
| 2022-2023 | $615,942 | $51,000 | 28.904 | $14,741 | +0.07% |
| 2021-2022 | $549,569 | $51,000 | 28.884 | $14,731 | +3.07% |
The complete history of permits filed for 16 William Avenue, Islip, including new construction or demolition permits, plus any work pertaining to plumbing, heating and sprinkler systems is available with a free account. Available data goes back to 1990.
Create a free account to unlock extended information for 16 William Avenue, Islip, including whether it's located in FEMA flood zones, floodways or special flood hazard areas, as well as the Coastal barriers resources system area (COBRA).
| FEMA flood zone(s) | X (See more on map) |
Access the detailed traffic volume map for 16 William Avenue, Islip to see estimated average daily traffic on streets surrounding the property as well as the types of properties in its vicinity.
| View daily traffic map |
| Name | Rating | Type | Grade range | No of students | Distance (miles) |
|---|---|---|---|---|---|
| Wing Elementary School | NR | Public | K-1 | 379 | 0.23 |
| Commack Road Elementary School | 3 | Public | 2-5 | 397 | 0.73 |
| St Mary School | NR | Private | PK-8 | 413 | 0.96 |
| St Mary School | NR | Private | PK-8 | 413 | 0.96 |
| Maud S Sherwood Elementary School | 6 | Public | 2-5 | 335 | 1.32 |
| Name | Rating | Type | Grade range | No of students | Distance (miles) |
|---|---|---|---|---|---|
| Islip Middle School | 4 | Public | 6-8 | 641 | 0.87 |
| St Mary School | NR | Private | PK-8 | 413 | 0.96 |
| St Patrick School | NR | Private | PK-8 | 534 | 1.59 |
| East Islip Middle School | 6 | Public | 6-8 | 804 | 1.71 |
| Bay Shore Middle School | 5 | Public | 6-8 | 1,298 | 2.18 |
| Name | Rating | Type | Grade range | No of students | Distance (miles) |
|---|---|---|---|---|---|
| Islip High School | 9 | Public | 9-12 | 892 | 0.81 |
| East Islip High School | 8 | Public | 9-12 | 1,145 | 1.74 |
| Bay Shore Senior High School | 5 | Public | 9-12 | 1,910 | 2.30 |
| MDQ Academy | NR | Private | PK-12 | 412 | 2.97 |
| Brentwood High School | 3 | Public | 9-12 | 4,641 | 3.39 |
Data provided by GreatSchools.org © 2025. All rights reserved.
Here are the neighbors for 16 William Avenue, Islip.
| Address | Square feet | Purchase date | Purchase price |
|---|---|---|---|
| 74 Winganhauppaugerd, Islip | 930 | 01/14/2022 | $425,000 |
| 24 William Ave, Islip | 10/19/2016 | $399,930 | |
| 11 Wallace St, Islip | 1,848 | 06/01/2016 | $295,000 |
| 285 Grant Ave, Islip | 01/20/2011 | $327,500 | |
| 356 Collington Dr, Ronkonkoma | 2,054 | 12/28/2018 | $407,000 |
| 378 Ontario St, Ronkonkoma | 1,468 | ||
| 86 Winganhauppaugerd, Islip | |||
| 99 Winganhauppaugerd, Islip | |||
| 91 Winganhauppaugerd, Islip | 08/03/2015 | ||
| 20 James St, Islip | 06/28/2013 | ||
| 4 Wallace St, Islip | 1,340 | 06/18/2018 | $315,000 |
| 66 Winganhauppaugerd, Islip | 2,110 | 08/04/2021 | |
| 395 Ontario St, Ronkonkoma | 01/06/2016 | $333,000 | |
| 390 Ontario St, Ronkonkoma | 1,126 | 10/10/2019 | $386,000 |
| 81 Winganhauppaugerd, Islip | |||
| 16 James St, Islip | 08/01/2016 | $349,990 | |
| 121 Commack Rd, Islip | 09/30/2024 | $620,000 | |
| 391 Ontario St, Ronkonkoma | 04/28/2023 | $446,000 | |
| 380 Ontario St, Ronkonkoma | 1,032 | 03/13/2017 | $336,000 |
| 90 Winganhauppaugerd, Islip | 760 | 08/19/2021 |