Most conversations about Sea Isle City real estate start with a gut feeling — which blocks are "hot," which homes are "old," what something is "worth." The numbers underneath those instincts are public. Here's what they actually say.
Everything below comes from one source: the NJGIN Parcels Composite, which lists 6,666 parcels in Sea Isle City. No modeling, no projections, no interpretation beyond describing what the data contains.
When Sea Isle was built
Of the 6,666 parcels, 5,941 have a recorded year of construction. The island's building history isn't evenly distributed — two decades account for 60% of the housing stock.
| Decade | Parcels | Share |
|---|---|---|
| Pre-1950 | 283 | 4.8% |
| 1950s | 102 | 1.7% |
| 1960s | 183 | 3.1% |
| 1970s | 732 | 12.3% |
| 1980s | 1,907 | 32.1% |
| 1990s | 791 | 13.3% |
| 2000s | 1,657 | 27.9% |
| 2010s | 186 | 3.1% |
| 2020s | 100 | 1.7% |
The 1980s produced nearly a third of the island's current structures. The 2000s produced another 28%. Together, those two decades account for 3,564 of the 5,941 parcels with a recorded year built.
1,300 parcels — 22% of the total — were built before 1980.
Housing age by street range
Age distribution shifts depending on where you are on the island. Below, each row groups the 5,922 parcels that have both a year built and an extractable block number. ¹
| Street range | Parcels | Pre-1980 | Median year built | Median assessed |
|---|---|---|---|---|
| 1st–19th | 268 | 50% | 1980 | $459,000 |
| 20th–39th | 1,094 | 32% | 1982 | $470,700 |
| 40th–59th | 1,996 | 20% | 1992 | $636,000 |
| 60th–79th | 1,558 | 11% | 1993 | $657,600 |
| 80th–93rd | 1,006 | 25% | 1987 | $661,100 |
The 1st–19th block range has the highest concentration of pre-1980 parcels at 50%. The 60th–79th range has the lowest at 11%.
The 40th–59th range holds the most parcels — 1,996 — making it the densest section of the island by parcel count.
Assessed value by construction era
Net assessed value (land plus improvements) from the NJGIN Parcels Composite, grouped by year of construction. ²
| Construction era | Parcels | Median assessed value |
|---|---|---|
| Pre-1980 | 1,300 | $458,200 |
| 1980–1999 | 2,698 | $552,800 |
| 2000–present | 1,943 | $702,200 |
The gap between the pre-1980 median ($458,200) and the 2000-and-later median ($702,200) is $244,000.
Land share of assessed value
The NJGIN Parcels Composite breaks assessed value into two components: land value (LAND_VAL) and improvement value (IMPRVT_VAL). The land share — land as a percentage of the sum — shows how much of a property's assessed value is in the lot itself versus the structure on it.
Of the 6,666 parcels, 6,665 have both values recorded. Across those, the median land share is 69.7%. The table below covers the 6,534 parcels with both values and an extractable block number.
| Street range | Parcels | Median land share | Median land value | Median improvement value |
|---|---|---|---|---|
| 1st–19th | 318 | 76.3% | $336,300 | $88,800 |
| 20th–39th | 1,194 | 68.6% | $287,400 | $129,100 |
| 40th–59th | 2,161 | 67.0% | $368,200 | $194,600 |
| 60th–79th | 1,806 | 69.9% | $373,200 | $192,400 |
| 80th–93rd | 1,055 | 72.2% | $455,800 | $172,000 |
Land share also varies by construction era. The 5,941 parcels with both values and a recorded year built break down as follows:
| Construction era | Parcels | Median land share |
|---|---|---|
| Pre-1980 | 1,300 | 83.5% |
| 1980–1999 | 2,698 | 70.3% |
| 2000–present | 1,943 | 55.6% |
For pre-1980 parcels, the median land share is 83.5% — land accounts for more than four-fifths of the total assessed value. For parcels built 2000 or later, it drops to 55.6%.
What this doesn't tell you
Assessed value is not market value. The NJGIN Parcels Composite is a tax assessment record — it reflects the municipality's valuation for tax purposes, not what a property would sell for today. The relationship between assessed value and sale price varies by property, block, and condition.
This data also doesn't include flood zone designations or recent sale prices. Those come from other sources.
If you want to understand what a specific property's lot is worth to a developer, that requires looking at the parcel in context — not just its assessed value, but what's been built nearby and what the lot supports.
Check your lot — free, no obligation.
Frequently Asked Questions
How many parcels are in Sea Isle City?
The NJGIN Parcels Composite lists 6,666 parcels in Sea Isle City. Of those, 5,941 have a recorded year of construction.
What percentage of Sea Isle City homes were built before 1980?
22% of Sea Isle City parcels with a recorded year built (1,300 of 5,941) were built before 1980, per the NJGIN Parcels Composite.
What is the median assessed value in Sea Isle City?
The median net assessed value across all Sea Isle City parcels in the NJGIN Parcels Composite is $598,400.
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¹ Block assignment is derived from the street number in each parcel's address. Parcels on numbered streets (e.g. "47TH ST") use that street number directly. Parcels on named avenues (Landis, Central, Pleasure, etc.) are assigned to the block by dividing the house number by 100 and rounding down — so 4515 Landis → block 45, 300 Sounds Ave → block 3. 19 parcels with a year built but no extractable block number are excluded from the housing-age street-range table; 131 parcels without an extractable block are excluded from the land-share street-range table.
² These three rows sum to 5,941 — the number of parcels with a recorded year of construction. The remaining 725 parcels have no year built in the NJGIN data.
Source: NJGIN Parcels Composite (NJ Office of GIS, hosted on ArcGIS). 6,666 parcels in Sea Isle City. Fields used: YR_CONSTR, LAND_VAL, IMPRVT_VAL, NET_VALUE, PROP_LOC. All figures are assessment values, not market values.