Population of Counties in New York (2021)
New York's most populous county in 2019 is Kings County, or the Brooklyn borough, with a population of 2,648,771. This represents growth of 5.49% since the 2010 census. New York is home to many counties and/or boroughs with more than 1 million people including Queens County (2,358,582), New York County (1,664,727), Suffolk County (1,492,953), Bronx County (1,471,160), and Nassau County (1,369,514). With the exception of Suffolk County (-0.12%), all of these counties have reported population growth of at least 2%.
New York Counties with Fewest Residents
Hamilton County is the least populated county in New York with 4,485 residents, a decline of 7.58% since the census. This is the only New York county under 15,000 people. There are a few other counties under 30,000 people in New York including Schuyler County (18,000), Yates County (24,955), and Lewis County (24,955). All of these counties -- in fact, all New York counties with fewer than 100,000 people -- have experienced a population decline.
New York Counties with Rapid Growth
Bronx County, which has the same boundaries as the Bronx borough, has experienced the most population growth since the census, increasing by 5.98% to 1,471,160. The only other counties with growth above 5% are Kings County and Queens County (5.49% each) and Rockland County (5.22%). Most counties in New York have lost residents since the 2010 census. The county that has experienced the greatest decline since 2010 is Hamilton County at -7.58% growth to 4,485. Other major declines occurred in Delaware County (-6.03%) and Chenango County (-5.03%).