County	Founded	Parent County	County Seat
Albany	1683	Original County	Albany
Allegany	1806	Genesee	Belmont
Bronx	1914	New York	Bronx
Broome	1806	Tioga	Binghamton
Cattaraugus	1808	Genesee	Little Valley
Cayuga	1799	Onondaga	Auburn
Charlotte	1772	Albany, renamed Washington in 1784	-
Chautauqua	1808	Genesee	Mayville
Chemung	1798	Tioga	Elmira
Chenango	1798	Herkimer, Tioga	Norwich
Clinton	1788	Washington	Plattsburgh
Columbia	1786	Albany	Hudson
Cortland	1808	Onondoga	Cortland
Delaware	1797	Ulster, Otsego	Delhi
Dutchess	1683	Original County	Poughkeepsie
Erie	1821	Niagara	Buffalo
Essex	1799	Clinton	Elizabethtown
Franklin	1808	Clinton	Malone
Fulton	1838	Montgomery	Johnstown
Genesee	1802	Ontario	Batavia
Greene	1800	Ulster, Albany	Catskill
Hamilton	1816	Montgomery	Lake Pleasant
Herkimer	1791	Montgomery	Herkimer
Jefferson	1805	Oneida	Watertown
Kings Brooklyn	1683	Original County	Brooklyn
Lewis	1805	Oneida	Lowville
Livingston	1821	Genesee, Ontario	Geneseo
Madison	1806	Chenango	Wampsville
Monroe	1821	Genesee, Ontario	Rochester
Montgomery	1772	Albany (as Tryon to 1784)	Fonda
Nassau	1899	Queens	Mineola
New York City (Manhattan)	1683	Original County	New York
Niagara	1808	Genesee	Lockport
Oneida	1798	Herkimer	Utica
Onondaga	1794	Herkimer	Syracuse
Ontario	1789	Montgomery	Canandaigua
Orange	1683	Original County	Goshen
Orleans	1824	Genesee	Albion
Oswego	1816	Oneida, Onondaga	Oswego, Pulaski
Otsego	1791	Montgomery	Cooperstown
Putnam	1812	Dutchess	Carmel
Queens	1683	Original County	Jamaica
Rensselaer	1791	Albany	Troy
Richmond Staten Island	1683	Original County	St. George
Rockland	1798	Orange	New City
St. Lawrence	1802	Clinton, Herkimer, Montgomery	Canton
Saratoga	1791	Albany	Ballston Spa
Schenectady	1809	Albany	Schenectady
Schoharie	1795	Albany, Ostego	Schoharie
Schuyler	1854	Tompkins, Steuben, Chemung	Watkins Glen
Seneca	1804	Cayuga	Ovid, Waterloo
Steuben	1796	Ontario	Bath
Suffolk	1683	Original County	Riverhead
Sullivan	1809	Ulster	Monticello
Tioga	1791	Montgomery	Owego
Tompkins	1817	Cayuga, Seneca	Ithaca
Tryon	1772	Albany, renamed Montgomery 1784	-
Ulster	1683	Original County	Kingston
Warren	1813	Washington	Lake George
Washington	1784	Albany, was named Charlotte from 1772 to 1784	Hudson Falls
Wayne	1823	Ontario, Seneca	Lyons
Westchester	1683	Original county	White Plains
Wyoming	1841	Genesee	Warsaw
Yates	1823	Ontario, Steuben	Penn Yan
Unknown County