New York

Suffolk

1,525,920
2020 population
1790
first census record
24
census records

About Suffolk

Suffolk, New York, first appears in the United States federal census in 1790, when it recorded a population of 16,440. At the most recent census, in 2020, its population stood at 1,525,920.

The county's recorded population has risen across the decades to its highest level in 2020.

On the ground today, 22 documented military engagements have been recorded within the county, among them Long Island Raiding Sites, Battle of Setauket Aug 22 1777, Meigs Raid on Sag Harbor, and 344 places are listed on the National Register of Historic Places.

Population by decade

Census YearPopulationChart
20201,525,920
20101,493,350
20001,419,369
19901,321,864
19801,284,231
19701,124,950
1960666,784
1950276,129
1940197,355
1930161,055
1920110,246
191096,138
190077,582
189062,491
188053,888
187046,924
186043,275
185036,922
184032,469
183026,780
182024,272
181021,113
180019,735
179016,440
Source

Population data from the United States decennial census, U.S. Census Bureau (public domain).

Battles & engagements in Suffolk

Military engagements that took place in Suffolk, New York.

Long Island Raiding Sites
1400
Battle of Setauket Aug 22 1777
1777
Meigs Raid on Sag Harbor
1777
Raid on Setauket
1777
Battle of Setauket
1777
Attack on Meigs at Sag Harbor
1777
Raid on Sag Harbor
1777
Raid on Sag Harbor (NY)
1777
Sag Harbor Raid
1777
Battle of Setauket (Long Island)
1777
Battle of Meigs Raid on Sag Harbor May 1777
1777
Long Island Skirmishes – Setauket
1777
Skirmish at Fort Franklin (Lloyd's Neck)
1779
Raid on Lloyd's Neck (Long Island)
1779
Raid on Fort St. George (Mastic, Long Island)
1780
Tallmadge's Raid on Fort St. George
1780
Battle of Fort St. George (1780)
1780
Raid on Fort Slongo (Fort Salonga)
1781
Raid on Lloyd Neck
1781
Battle of Fort Salonga
1781
Raid on Lloyd Neck (1781)
1781
German Saboteurs Landing at Amagansett
1942

Historic places in Suffolk

National Register of Historic Places listings in Suffolk, New York.

Conklin, David, House
Cold Spring Harbor
Buell's Lane Historic District
East Hampton
Commack Methodist Church and Cemetery
Huntington
First Presbyterian Church
Sag Harbor
Greenport Village Historic District
Greenport
Halsey Estate-Tallwood
West Hills
Hayground Windmill
East Hampton
Heckscher Park
Huntington
Velzer, N., House and Caretaker's Cottage
Centerport
USS SAN DIEGO (Armored Cruiser) Shipwreck Site
Fire Island
Harbor House
Nissequogue
Manhanset Chapel
Shelter Island
Big Duck, The
Flanders
Old Town Green Historic District
Huntington
Landon, Samuel, House
Southold
Old Town Hall Historic District
Huntington
Ockers, Jacob, House
Oakdale
Vail-Leavitt Music Hall
Riverhead
Longbotham, Nathaniel, House
Stony Brook
Long Island National Cemetery
Farmingdale
Land of Clover
Nissequogue
Homan-Gerard House and Mills
Yaphank
Mallows, The
Head of the Harbor
Mills Pond District
St. James
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Other counties in New York

Explore census history and historic records for more New York counties.

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Everything a full report reveals about Suffolk County, New York

This page charts the census history of Suffolk County, New York. A full Aubrey report for an address here pulls together everything the historical record holds about the ground, from the earliest settlement to the twentieth century:

Overview
An interactive map of the location with historic sites, battles and Native heritage plotted, and its full story era by era.
The Land
The historic sites and place names around the location, and how this land was settled and used.
Geology
The bedrock beneath the site, its age and rock type, reaching back millions of years.
LiDAR Terrain
Laser-scanned terrain that reveals earthworks and old features hidden in the landscape.
Conflict & War
The battles, raids and skirmishes fought near here, across every era of American conflict.
The Civil War
The Civil War on this ground, 1861 to 1865: who held it, and the battles, camps and regiments nearby.
The Soldiers
The men who marched from here in the Civil War, named and traced where the record allows.
Native Heritage
The Native nations who held this land, mapped across time from before European contact to today.
Settlement
Who claimed and held this ground, from Indigenous homelands through the colonial powers to the United States.
The Community
How the town grew, who came, and what kind of place it became, traced through the census record.
Rivers & Rail
The rivers, canals and railroads that connected this place between 1830 and 1911.
Notable People
The people born, buried or genuinely tied to this exact place, with their stories.
Historical Maps
Historic maps of the location layered over how it looks today.
Finds & Access
Museum objects tied to the area, and the laws on searching, collecting and access here.
Literature
The old books, county histories and archives that mention this place, quoted with their sources.
Spotlight
A deep dive into the most remarkable, lesser-known history of the place, traced back to the record.
Points of Interest
The most significant historic sites and landmarks near the location, and why they matter.
Timeline
The whole story of the location told era by era, from first peoples to the present day.
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Frequently asked about Suffolk

When does Suffolk first appear in the US census?
Suffolk, New York first appears in the federal census in 1790, with a recorded population of 16,440.
What is the population of Suffolk?
At the most recent federal census (2020), Suffolk had a recorded population of 1,525,920.
Were any battles fought in Suffolk?
22 documented military engagements took place in Suffolk, including Long Island Raiding Sites, Battle of Setauket Aug 22 1777, Meigs Raid on Sag Harbor.
How many historic places are in Suffolk?
344 sites are listed on the National Register of Historic Places in Suffolk, New York.
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