Nassau County, New York

Nassau County is a county in New York, United States, on western Long Island directly east of New York City. It had a population of 1,395,774 at the 2020 census, an estimated 1,398,939 by 2025, and covers 285 square miles of land (738 km2) centred near 40°44′N 73°38′W.

Mineola is the county seat, an incorporated village of its own; its postal code is 11501. The county holds 2 cities, 64 incorporated villages and dozens of unincorporated hamlets grouped into 3 towns, and it runs on Eastern Time. Its FIPS code is 36059.

Towns & Villages in Nassau County

Nassau packs more than 130 named places into 285 square miles — more than any other county on this site. The table below ranks the 30 largest by 2020 population; dozens more incorporated villages (New Hyde Park, Farmingdale, Island Park, Great Neck Estates, Kings Point and others) and smaller hamlets fill out the rest. “Unincorp.” marks a Census-designated place with no village government of its own — it is administered directly by its town.

Two name pairs trip people up. Massapequa (an unincorporated CDP, 21,355 people) and Massapequa Park (an incorporated village next door, 17,109) are separate places with separate governments, and a third, North Massapequa, is a smaller unincorporated CDP again. Great Neck the village (11,145) is only one of nine Great Neck villages and hamlets clustered on the peninsula — Great Neck Estates, Great Neck Plaza, Kings Point and others are each their own municipality.

Towns

New York towns are the county’s primary civil divisions — every acre of Nassau outside its two independent cities belongs to one of three. Each contains a mix of self-governing incorporated villages and unincorporated hamlets the town itself administers.

Hempstead is the most populous town in New York, outsizing the other two combined. Glen Cove and Long Beach sit outside all three — as cities, they are independent of town government entirely, a distinction New York shares with few other states.

ZIP Codes

• 11550 — Hempstead (also serves parts of Uniondale)
• 11756 — Levittown
• 11520 — Freeport
• 11801 — Hicksville
• 11580 — Valley Stream
• 11554 — East Meadow
• 11003 — Elmont
• 11561 — Long Beach
• 11510 — Baldwin
• 11572 — Oceanside
• 11553 — Uniondale
• 11010 — Franklin Square
• 11542 — Glen Cove
• 11803 — Plainview
• 11570 — Rockville Centre
• 11530 — Garden City
• 11566 — Merrick
• 11758 — Massapequa
• 11501 — Mineola
• 11563 — Lynbrook
• 11552 — West Hempstead
• 11791 — Syosset
• 11793 — Wantagh
• 11714 — Bethpage
• 11710 — Bellmore
• 11590 — Westbury
• 11021–11025 — the nine Great Neck villages and hamlets, split across five codes

The smaller Great Neck-peninsula villages and several North Hempstead hamlets share a post office town’s ZIP rather than holding one of their own — Saddle Rock, Thomaston and Russell Gardens all mail through Great Neck’s 11021–11024 range.

Geography

Nassau sits on the western third of Long Island, a low glacial outwash plain built by two ice-age moraines. The Harbor Hill Moraine runs along the North Shore, giving Glen Cove, Port Washington and the Gold Coast estates their bluffs and inlets on Long Island Sound; the flatter South Shore faces the Atlantic across a chain of barrier beaches — Jones Beach and Long Beach among them — enclosing the shallow Hempstead Bay and Great South Bay. The now-developed Hempstead Plains, once the only natural prairie east of the Appalachians, covers the county’s flat central spine.

Nassau borders Queens, one of New York City’s five boroughs, to the west, and Suffolk County to the east. Long Island Sound forms its northern shoreline, facing Westchester County and Connecticut across open water, and the Atlantic Ocean bounds it on the south.

Demographics

Nassau County had 1,395,774 residents at the 2020 census, the sixth-highest county total in New York, and an estimated 1,398,939 by 2025 — essentially flat growth. Hempstead Village (59,169) and Levittown (51,758) are its two largest communities. Population density runs about 4,898 people per square mile of land, among the densest suburban counties in the country. Median household income was $116,100 (2019 ACS 5-year estimate), well above the New York statewide median of roughly $72,100 over the same period.

Economy & Local Life

Healthcare is the county’s largest employer sector: Northwell Health, New York State’s biggest healthcare provider, is headquartered in New Hyde Park, and NYU Langone Hospital–Long Island anchors Mineola. Retail centers on Roosevelt Field in Garden City, one of the largest shopping malls in the United States by leasable area. Aerospace has deep roots in Bethpage, where Grumman (now part of Northrop Grumman) built Navy fighters and, during the Apollo program, the lunar module; the former Grumman campus is now a mixed commercial park. Most working residents commute west into Manhattan by rail. The county’s biggest annual public draw is the Bethpage Air Show over Jones Beach each Memorial Day weekend.

History

Nassau County was carved out of Queens County effective January 1, 1899, after Queens’ three westernmost towns joined the 1898 consolidation that created Greater New York City, leaving Hempstead, North Hempstead and Oyster Bay as an orphaned rump. The new county took its name from the House of Orange-Nassau, honoring King William III of England, a name already attached informally to the region since the colonial era. From the 1890s through the 1930s its North Shore — nicknamed the Gold Coast — filled with the estates of the Vanderbilts, Whitneys and Woolworths; F. Scott Fitzgerald, living in Great Neck in the early 1920s, drew on it for The Great Gatsby. Charles Lindbergh took off from Roosevelt Field on May 20, 1927, for the first solo transatlantic flight. After World War II, Levitt & Sons built Levittown between 1947 and 1951, roughly 17,400 near-identical houses that became the template for mass-produced American suburbs.

Getting There

The Long Island Expressway (I-495) crosses northern Nassau; the Northern State, Southern State, Meadowbrook State and Wantagh State parkways run north-south but bar commercial trucks, a Robert Moses-era design choice still in force. The Long Island Rail Road serves the county far more densely than the road network suggests, with the Main, Hempstead, Oyster Bay, Port Washington and West Hempstead branches stopping at dozens of stations, most within 35–45 minutes of Manhattan.

• Manhattan — 21 miles west of Hempstead Village
• Jamaica, Queens — 12 miles west of Hempstead Village
• Huntington, Suffolk County — 14 miles east of Oyster Bay hamlet
• Babylon, Suffolk County — 15 miles east of Massapequa

LaGuardia Airport and John F. Kennedy International Airport, both roughly 15–20 miles away in neighboring Queens, are the nearest commercial airports; Long Island MacArthur Airport in Suffolk County is a smaller alternative. Nassau has no Amtrak station of its own — the LIRR connects to Amtrak service at Penn Station in Manhattan.

Frequently Asked Questions

Where is Nassau County?
It occupies the western third of Long Island in New York, bordered by Queens to the west, Suffolk County to the east, Long Island Sound to the north and the Atlantic Ocean to the south.

What is the population of Nassau County?
It had a population of 1,395,774 at the 2020 census, estimated at 1,398,939 by 2025.

How big is Nassau County?
It covers 285 square miles (738 km2) of land, plus another 169 square miles of bay, harbor and sound waters.

What is the county seat of Nassau County?
Mineola, an incorporated village in the Town of North Hempstead, is the county seat.

How many towns and villages are in Nassau County?
Three towns — Hempstead, North Hempstead and Oyster Bay — plus 2 independent cities (Glen Cove and Long Beach) and 64 incorporated villages, alongside dozens of unincorporated hamlets.

Which ZIP codes does Nassau County use?
Its largest places run from 11003 (Elmont) through 11803 (Plainview); see the ZIP Codes section above for the full list of post office towns.

Is Levittown in Nassau County?
Yes. Levittown, built 1947–1951 in the Town of Hempstead, was the first mass-produced suburban development in the United States and remains one of the county’s largest unincorporated communities at 51,758 residents.

More counties in this state: Towns and villages in New York.