Suffolk County, New York


Suffolk County is the easternmost county in the U.S. state of New York, constituting the eastern two-thirds of Long Island. It is bordered to its west by Nassau County, to its east by Gardiners Bay and the open Atlantic Ocean, to its north by Long Island Sound, and to its south by the Atlantic Ocean.
As of the 2020 United States census, the county's population was 1,525,920, its highest decennial count ever, making Suffolk the fourth-most populous county in the State of New York, and the most populous outside of the boroughs of New York City. Its county seat is Riverhead, though most county offices are in Hauppauge. The county was named after the county of Suffolk in England, the origin of its earliest European settlers.
Suffolk County incorporates the easternmost extreme of both the New York City metropolitan area and New York State. The geographically largest of Long Island's four counties and the second-largest of New York's 62 counties, Suffolk County is in length and in width at its widest. Most of the island is near sea level, with over of coastline.
Like other parts of Long Island, the county's high population density and proximity to New York City has resulted in a diverse economy, including industry, science, agriculture, fishery, and tourism. Major scientific research facilities in Suffolk County include Brookhaven National Laboratory in Upton and Plum Island Animal Disease Center on Plum Island. The county is home to Stony Brook University in Stony Brook and Farmingdale State College in East Farmingdale.

History

Suffolk County was part of the Connecticut Colony before becoming an original county of the Province of New York, one of twelve created in 1683. From 1664 until 1683, it had been the East Riding of Yorkshire. Its boundaries were essentially the same as at present, with only minor changes in the boundary with its western neighbor, which was originally Queens County but has been Nassau County since the separation of Nassau from Queens in 1899.
During the American Revolutionary War, Great Britain occupied Suffolk County after the retreat of George Washington's forces in the Battle of Long Island, and the county remained under occupation until the British evacuation of New York on November 25, 1783.
According to the Suffolk County website, the county is the leading agricultural county in the state of New York, saying that: "The weather is temperate, clean water is abundant, and the soil is so good that Suffolk is the leading agricultural county in New York State. That Suffolk is still number one in farming, even with the development that has taken place, is a tribute to thoughtful planning, along with the excellent soil, favorable weather conditions, and the work of the dedicated farmers in this region."

Geography

According to the U.S. Census Bureau, the county has an area of, of which is land and is water. It is the second-largest county in New York by total area and occupies 66% of the land area of Long Island.
Suffolk County occupies the central and eastern part of Long Island, in the extreme east of the State of New York. The eastern end of the county splits into two peninsulas, known as the North Fork and the South Fork. The county is surrounded by water on three sides, including the Atlantic Ocean and Long Island Sound, with of coastline. The eastern end contains large bays.
The highest elevation in the county, and on Long Island as a whole, is Jayne's Hill in West Hills, at above sea level. This low lying-geography means that much of the county is vulnerable to sea level rise.

Climate

Suffolk County sits at the convergence of climate zones including the humid continental and humid subtropical, bordering closely on an oceanic climate. The majority of the county by land area is in the Dfa zone. Summers are cooler at the east end than in the western part of the county. The hardiness zone is 7a, except in Copiague Harbor, Lindenhurst, and Montauk, where it is 7b. Average monthly temperatures in Hauppauge range from in January to in July, and in the Riverhead town center they range from in January to in July, which includes both daytime and nighttime temperatures. On February 9, 2013, Suffolk County was besieged with 30 inches of snow, making it the largest day of snowfall on record in Suffolk.

Adjacent counties

Suffolk County has maritime boundaries with five other U.S. counties and is connected by land only to Nassau County.

Race and ethnicity

2010 census

According to the 2010 U.S. census there were 1,493,350 people and 569,985 households residing in the county. The census estimated Suffolk County's population decreased slightly to 1,481,093 in 2018, representing 7.5% of the census-estimated New York State population of 19,745,289 and 19.0% of the census-estimated Long Island population of 7,869,820. The population density in 2010 was, with 569,985 households at an average density of. However, by 2012, with an estimated total population increasing moderately to 1,499,273 there were 569,359 housing units. As of 2006, Suffolk County was the 21st-most populous county in the United States.
By 2014, the county's racial makeup was estimated at 85.2% White, 8.3% African American, 0.6% Native American, 4.0% Asian, 0.1% Pacific Islander, and 1.8% from two or more races. Those identifying as Hispanic or Latino, of any race, were 18.2% of the population. Those who identified as "white alone", not being of Hispanic or Latino origin, represented 69.3% of the population. In 2006, the county's racial or ethnic makeup was 83.6% White. African Americans were 7.4% of the population. Asians stood at 3.4% of the population. 5.4% were of other or mixed race. Latinos were 13.0% of the population. In 2007, Suffolk County's most common ethnicities were Italian, Irish, and German.
In 2002, The New York Times cited a study by the non-profit group ERASE Racism, which determined Suffolk and its neighboring county, Nassau, to be the most racially segregated suburbs in the United States.
In 2006, there were 469,299 households, of which 37.00% had children under the age of 18 living with them, 62.00% were married couples living together, 10.80% had a female householder with no husband present, and 23.20% were non-families. 18.30% of all households were made up of individuals, and 7.80% had someone living alone who was 65 years of age or older. The average household size was 2.96 and the average family size was 3.36.
In the county, the population was spread out, with 26.10% under the age of 18, 7.60% from 18 to 24, 31.20% from 25 to 44, 23.30% from 45 to 64, and 11.80% who were 65 years of age or older. The median age was 36 years. For every 100 females, there were 95.90 males. For every 100 females age 18 and over, there were 92.80 males.
In 2008, Forbes magazine released its American Community Survey and named Suffolk County number 4 in its list of the top 25 richest counties in America. In 2016, according to Business Insider, the 11962 zip code encompassing Sagaponack, within Southampton, was listed as the most expensive in the U.S., with a median home sale price of $8.5 million.
The median income for a household in the county was $84,767, and the median income for a family was $72,112. Males had a median income of $50,046 versus $33,281 for females. The per capita income for the county was $26,577. Using a weighted average from 2009 to 2014 about 6.40% of the population were below the poverty line. In earlier censuses, the population below the poverty line included 2.70% of those under age 18 and 2.30% of those age 65 or over.

Law and government

Active Voter Registration and Party Enrollment as of February 20, 2025Active Voter Registration and Party Enrollment as of February 20, 2025Active Voter Registration and Party Enrollment as of February 20, 2025Active Voter Registration and Party Enrollment as of February 20, 2025Active Voter Registration and Party Enrollment as of February 20, 2025Active Voter Registration and Party Enrollment as of February 20, 2025
PartyPartyNumber of votersPercentage--
Democratic360,67133.21%--
Republican341,00831.40%--
Unaffiliated327,37330.14%--
Conservative20,6411.90%--
Working Families4,1780.38%--
Other32,1702.96%--
TotalTotal1,086,041100%--

State Senate Officials for Suffolk County

State Assembly Officials for Suffolk County

United States House of Representatives Officials for Suffolk County

United States Senate

In 2003, Democrat Steve Levy was elected county executive, ending longtime Republican control. In 2001, Democrat Thomas Spota was elected District Attorney, and ran unopposed in 2005. Although Suffolk voters gave George H. W. Bush a victory here in 1992, the county voted for Bill Clinton in 1996 and continued the trend by giving Al Gore an 11-percent victory in the county in 2000. 2004 Democratic candidate John Kerry won by a much smaller margin of under one percent, in 2008 Democratic candidate Barack Obama won by a slightly larger 6 percent margin, 52.5%-46.5%. In 2012, he carried the county by a slightly smaller margin 51%-47%. In 2016, Republican candidate Donald Trump won Suffolk County by a 6.9 percent margin, becoming the first Republican to carry the county since 1992. In 2020, Trump again won Suffolk County; this time, however, it was decided by just 232 votes out of nearly 800,000 votes cast, making it the closest county in the nation in terms of percentage margin, and representing nearly a seven-point swing towards the Democratic ticket of former Vice President Joe Biden and junior California senator Kamala Harris. In percentage terms, it was the closest county in the state, although Ontario County and Warren County had narrower raw vote margins of just 33 and 57 votes, respectively. Suffolk was one of five counties in the state that Trump won by less than 500 votes. With Tarrant County, Texas and Maricopa County, Arizona flipping Democratic in 2020, Suffolk County was the most populous county in the nation to vote for Trump in 2020. In 2024, Trump won 54% of the vote in Suffolk county, the highest percentage since 1988.
As a whole, both Suffolk and Nassau counties are considered swing counties. However, until 2016, they tended not to receive significant attention from presidential candidates, as the state of New York has turned reliably Democratic at the national level. In 2008 and 2012, Hofstra University in Nassau County hosted a presidential debate. Hofstra hosted the first debate of the 2016 presidential election season, on September 26, 2016, making Hofstra the first college or university in the United States to host a presidential debate in three consecutive elections. The presence on the 2016 ticket of Westchester County resident Hillary Clinton and Manhattan resident Donald Trump resulted in greater attention by the candidates to the concerns of Long Island. Trump visited Long Island voters and donors at least four times while Clinton made one stop for voters and one additional stop in the Hamptons for donors.
After the 2022 midterm election results were counted, Suffolk appears to have moved further to the right. Republican gubernatorial candidate and Suffolk County native Lee Zeldin won the county by more than 17 points over the Democratic candidate Kathy Hochul. Republicans, as of 2024, hold both congressional districts covering that being New York's 1st congressional district represented by Nick LaLota and New York's 2nd congressional district represented by Andrew Garbarino.
The 2023 election saw this trend continue, with Republican Edward P. Romaine defeating Democrat David Calone by 14 points to become the next County Executive. Republicans also gained a 12-6 supermajority in the County Legislature, seeing a net gain of one seat.