Population & Demographics by Long Island Town
This page provides population and core demographic statistics for all 13 civil towns in Nassau County and Suffolk County on Long Island. The tables include estimated population, median household income, median age, and the percentage of adults age 25 and older who have earned a bachelor’s degree or higher.
The figures come from the latest available U.S. Census Bureau American Community Survey releases. The 2024 ACS 1-year estimates are used where available, while the 2020-2024 ACS 5-year estimates are used for towns that do not receive 1-year statistics.
Source: U.S. Census Bureau American Community Survey, including 2024 ACS 1-year estimates and 2020-2024 ACS 5-year estimates.
Important: These statistics are presented for Long Island’s 13 civil towns rather than individual villages, hamlets, census-designated places (CDPs), or cities. For population information on individual communities, see our Long Island Municipalities, Villages & Hamlets guide. American Community Survey (ACS) figures are survey estimates rather than exact population counts, and margins of error apply. Small differences between towns or survey releases should therefore be interpreted cautiously.
Although Brooklyn and Queens are geographically located on Long Island, they are boroughs of New York City and are not organized as civil towns. They are not included in these Nassau County and Suffolk County tables.
Methodology
- 2024 ACS 1-year estimates are used for Hempstead, North Hempstead, Oyster Bay, Brookhaven, Islip, Huntington, Babylon, Smithtown, and Southampton.
- 2020-2024 ACS 5-year estimates are used for East Hampton, Riverhead, Southold, and Shelter Island because 1-year estimates are not published for those smaller towns.
- Population is the ACS estimate of the town’s resident population.
- Median household income is expressed in inflation-adjusted dollars for the applicable ACS release.
- Median age represents the estimated age that divides the town’s population into two numerically equal groups.
- Bachelor’s degree or higher is the percentage of residents age 25 and older who hold a bachelor’s, graduate, or professional degree.
- Because 1-year and 5-year ACS products cover different periods, comparisons between towns should be treated as general demographic comparisons rather than measurements from one identical survey period.
- Figures have been rounded for readability. Census margins of error are not reproduced in the tables but remain applicable to every estimate.
Nassau County Towns
| Town | Population | Median Household Income | Median Age | Bachelor’s Degree or Higher | ACS Source |
|---|---|---|---|---|---|
| Hempstead | 792,369 | $137,709 | 41.1 | 46.0% | 2024 1-year |
| North Hempstead | 237,680 | $166,670 | 43.2 | 62.5% | 2024 1-year |
| Oyster Bay | 299,530 | $152,258 | 43.4 | 57.1% | 2024 1-year |
Suffolk County Towns
| Town | Population | Median Household Income | Median Age | Bachelor’s Degree or Higher | ACS Source |
|---|---|---|---|---|---|
| Brookhaven | 492,778 | $115,085 | 39.8 | 35.1% | 2024 1-year |
| Islip | 339,154 | $127,643 | 38.2 | 31.8% | 2024 1-year |
| Huntington | 204,696 | $166,827 | 45.5 | 54.3% | 2024 1-year |
| Babylon | 218,565 | $125,522 | 41.7 | 33.6% | 2024 1-year |
| Smithtown | 116,240 | $145,754 | 40.6 | 59.9% | 2024 1-year |
| Southampton | 70,645 | $121,111 | 50.6 | 47.3% | 2024 1-year |
| East Hampton | 28,701 | $132,348 | 46.3 | 53.7% | 2020-2024 5-year |
| Riverhead | 35,980 | $94,249 | 52.1 | 29.4% | 2020-2024 5-year |
| Southold | 23,905 | $116,667 | 53.7 | 50.0% | 2020-2024 5-year |
| Shelter Island | 3,355 | $133,967 | 50.0 | 63.0% | 2020-2024 5-year |
Understanding the Town-Level Differences
Long Island’s town-level demographic profile reflects the region’s combination of densely developed suburban communities, established commuter areas, waterfront neighborhoods, rural districts, and seasonal destinations. Hempstead is by far the most populous town in Nassau or Suffolk County, while Brookhaven is the largest Suffolk County town by population. Islip, Oyster Bay, North Hempstead, Babylon, and Huntington also contain substantial year-round populations.
The smaller East End towns generally have older populations and fewer year-round residents. Riverhead, Southold, East Hampton, Southampton, and Shelter Island include communities where seasonal housing, retirement-age residents, second homes, agricultural land, and coastal development can influence local demographic patterns.
Household income and educational attainment also vary significantly. North Hempstead and Huntington report some of the highest median household incomes in the tables, while North Hempstead, Smithtown, Oyster Bay, Huntington, East Hampton, Southold, and Shelter Island have comparatively high percentages of adults with bachelor’s degrees or higher. Estimates for small towns, particularly Shelter Island, can carry substantial margins of error and should not be treated as exact rankings.
These figures provide a useful current overview of the towns that make up Nassau County and Suffolk County, but they should be considered alongside the U.S. Census Bureau’s published margins of error, geographic definitions, and release notes when used for detailed research or formal reporting.
© 2026 LongIslandGuide.com • Compiled from U.S. Census Bureau American Community Survey data. Figures should be reviewed following each annual ACS release.
