County
| FIPS Code [4] | County Seat [5] | Created [5] | Formed from [1] | Named for [2] | Population [5] | Area [5] | Map |
| Albany County | 001 | Albany | 1683 | One of 12 original counties created in the New York colony | James II of England (James VII of Scotland) (1633–1701), who was Duke of York (English title) and Duke of Albany (Scottish title) before becoming King of England, Ireland, and Scotland. | &0000000000294565.000000294,565 | &0000000000000533.000000533 sq mi (&0000000000001380.0000001,380 km2) |  |
| Allegany County | 003 | Belmont | 1806 | Genesee County | A variant spelling of the Allegheny River | &0000000000049927.00000049,927 | &0000000000001034.0000001,034 sq mi (&0000000000002678.0000002,678 km2) |  |
| Bronx County | 005 | New York City (Coterminous with The Bronx) | 1914[6] | New York County | Jonas Bronck (1600?–1643), an early settler of the Dutch colony of New Amsterdam | &0000000001332650.0000001,332,650 | &0000000000000057.43000057.43 sq mi (&0000000000000149.000000149 km2) |  |
| Broome County | 007 | Binghamton | 1806 | Tioga County | John Broome (1738–1810), fourth Lieutenant Governor of New York | &0000000000200536.000000200,536 | &0000000000000715.000000715 sq mi (&0000000000001852.0000001,852 km2) |  |
| Cattaraugus County | 009 | Little Valley | 1808 | Genesee County | A Seneca word meaning "bad smelling banks," referring to the odor of natural gas which leaked from local rock formations | &0000000000083955.00000083,955 | &0000000000001310.0000001,310 sq mi (&0000000000003393.0000003,393 km2) |  |
| Cayuga County | 011 | Auburn | 1799 | Onondaga County | The Cayuga tribe of Native Americans | &0000000000081963.00000081,963 | &0000000000000694.000000694 sq mi (&0000000000001797.0000001,797 km2) |  |
| Chautauqua County | 013 | Mayville | 1808 | Genesee County | A Seneca word meaning "where the fish was taken out" | &0000000000136409.000000136,409 | &0000000000001062.0000001,062 sq mi (&0000000000002751.0000002,751 km2) |  |
| Chemung County | 015 | Elmira | 1836 | Tioga County | A Lenape word meaning "big horn", which was the name of a local Native American village | &0000000000091070.00000091,070 | &0000000000000410.810000410.81 sq mi (&0000000000001064.0000001,064 km2) |  |
| Chenango County | 017 | Norwich | 1798 | Tioga County and Herkimer County | An Onondaga word meaning "large bull-thistle" | &0000000000051401.00000051,401 | &0000000000000898.850000898.85 sq mi (&0000000000002328.0000002,328 km2) |  |
| Clinton County | 019 | Plattsburgh | 1788 | Washington County | George Clinton (1739–1812), fourth Vice President of the United States and first and third Governor of New York | &0000000000079894.00000079,894 | &0000000000001118.0000001,118 sq mi (&0000000000002896.0000002,896 km2) |  |
| Columbia County | 021 | Hudson | 1786 | Albany County | Christopher Columbus (1451–1506), the European explorer | &0000000000063094.00000063,094 | &0000000000000648.000000648 sq mi (&0000000000001678.0000001,678 km2) |  |
| Cortland County | 023 | Cortland | 1808 | Onondaga County | Pierre Van Cortlandt (1721–1814), first Lieutenant Governor of New York | &0000000000048599.00000048,599 | &0000000000000502.000000502 sq mi (&0000000000001300.0000001,300 km2) |  |
| Delaware County | 025 | Delhi | 1797 | Otsego County and Ulster County | Thomas West, 3rd Baron De La Warr (1577–1618), an early colonial leader in Virginia | &0000000000048055.00000048,055 | &0000000000001468.0000001,468 sq mi (&0000000000003802.0000003,802 km2) |  |
| Dutchess County | 027 | Poughkeepsie | 1683 | One of 12 original counties created in the New York colony | Lady Anne Hyde (1637–1671), Duchess of York and wife of King James II of England | &0000000000295146.000000295,146 | &0000000000000825.000000825 sq mi (&0000000000002137.0000002,137 km2) |  |
| Erie County | 029 | Buffalo | 1821 | Niagara County | The Erie tribe of Native Americans | &0000000000950265.000000950,265 | &0000000000001044.0000001,044 sq mi (&0000000000002704.0000002,704 km2) |  |
| Essex County | 031 | Elizabethtown | 1799 | Clinton County | The county of Essex in England | &0000000000038851.00000038,851 | &0000000000001916.0000001,916 sq mi (&0000000000004962.0000004,962 km2) |  |
| Franklin County | 033 | Malone | 1808 | Clinton County | Benjamin Franklin (1706–1790), the early American printer, scientist, and statesman | &0000000000051134.00000051,134 | &0000000000001697.0000001,697 sq mi (&0000000000004395.0000004,395 km2) |  |
| Fulton County | 035 | Johnstown | 1838 | Montgomery County | Robert Fulton (1765–1815), inventor of the steamship | &0000000000055073.00000055,073 | &0000000000000533.000000533 sq mi (&0000000000001380.0000001,380 km2) |  |
| Genesee County | 037 | Batavia | 1802 | Ontario County | A Seneca phrase meaning "good valley" | &0000000000060370.00000060,370 | &0000000000000495.000000495 sq mi (&0000000000001282.0000001,282 km2) |  |
| Greene County | 039 | Catskill | 1800 | Albany County and Ulster County | Nathanael Greene (1742–1786), the American Revolutionary War general | &0000000000048195.00000048,195 | &0000000000000658.000000658 sq mi (&0000000000001704.0000001,704 km2) |  |
| Hamilton County | 041 | Lake Pleasant | 1816 | Montgomery County | Alexander Hamilton (1755–1804), the early American political theorist and first Secretary of the Treasury | &0000000000005379.0000005,379 | &0000000000001808.0000001,808 sq mi (&0000000000004683.0000004,683 km2) |  |
| Herkimer County | 043 | Herkimer | 1791 | Montgomery County | Nicholas Herkimer (1728–1777), the American Revolutionary War general | &0000000000064427.00000064,427 | &0000000000001458.0000001,458 sq mi (&0000000000003776.0000003,776 km2) |  |
| Jefferson County | 045 | Watertown | 1805 | Oneida County | Thomas Jefferson (1743–1826), the early American statesman, author of the Declaration of Independence, and third President of the United States | &0000000000111738.000000111,738 | &0000000000001272.0000001,272 sq mi (&0000000000003294.0000003,294 km2) |  |
| Kings County | 047 | New York City (Coterminous with Brooklyn) | 1683 | One of 12 original counties created in the New York colony | King Charles II of England (1630–1685) | &0000000002465326.0000002,465,326 | &0000000000000096.90000096.9 sq mi (&0000000000000251.000000251 km2) |  |
| Lewis County | 049 | Lowville | 1805 | Oneida County | Morgan Lewis (1754–1844), the fourth Governor of New York | &0000000000026944.00000026,944 | &0000000000001290.0000001,290 sq mi (&0000000000003341.0000003,341 km2) |  |
| Livingston County | 051 | Geneseo | 1821 | Genesee County and Ontario County | Robert Livingston (1746–1813), the early American statesman and New York delegate to the Continental Congress | &0000000000064328.00000064,328 | &0000000000000640.000000640 sq mi (&0000000000001658.0000001,658 km2) |  |
| Madison County | 053 | Wampsville | 1806 | Chenango County | James Madison (1751–1836), the early American statesman, principal author of the Constitution of the United States, and fourth President of the United States | &0000000000069441.00000069,441 | &0000000000000662.000000662 sq mi (&0000000000001715.0000001,715 km2) |  |
| Monroe County | 055 | Rochester | 1821 | Genesee County and Ontario County | James Monroe (1758–1831), the early American statesman and fifth President of the United States | &0000000000735343.000000735,343 | &0000000000000659.000000659 sq mi (&0000000000001707.0000001,707 km2) |  |
| Montgomery County | 057 | Fonda | 1772 | Albany County | Originally Tryon County after colonial governor William Tryon (1729–1788), renamed after the American Revolutionary War general Richard Montgomery (1738–1775) in 1784 | &0000000000049708.00000049,708 | &0000000000000410.000000410 sq mi (&0000000000001062.0000001,062 km2) |  |
| Nassau County | 059 | Mineola | 1899 | Queens County | William of Orange-Nassau (1650–1702), who became King William III of England | &0000000001334544.0000001,334,544 | &0000000000000287.000000287 sq mi (&0000000000000743.000000743 km2) |  |
| New York County | 061 | New York City (Coextensive with Manhattan) | 1683 | One of 12 original counties created in the New York colony | King James II of England (1633–1701), who was Duke of York and Albany before he ascended the throne of England, Duke of York being his English title | &0000000001537195.0000001,537,195 | &0000000000000033.77000033.77 sq mi (&0000000000000087.00000087 km2) |  |
| Niagara County | 063 | Lockport | 1808 | Genesee County | An Iroquoian word perhaps meaning "a neck" between two bodies of water, "thunder of waters," or "bisected bottom land" | &0000000000219846.000000219,846 | &0000000000000523.000000523 sq mi (&0000000000001355.0000001,355 km2) |  |
| Oneida County | 065 | Utica | 1798 | Herkimer County | The Oneida tribe of Native Americans | &0000000000235469.000000235,469 | &0000000000001213.0000001,213 sq mi (&0000000000003142.0000003,142 km2) |  |
| Onondaga County | 067 | Syracuse | 1792 | Herkimer County | The Onondaga tribe of Native Americans | &0000000000458336.000000458,336 | &0000000000000806.000000806 sq mi (&0000000000002088.0000002,088 km2) |  |
| Ontario County | 069 | Canandaigua | 1789 | Montgomery County | An Iroquoian word meaning "beautiful lake" | &0000000000100224.000000100,224 | &0000000000000662.000000662 sq mi (&0000000000001715.0000001,715 km2) |  |
| Orange County | 071 | Goshen | 1683 | One of 12 original counties created in the New York colony | William of Orange-Nassau (1650–1702), who became King William III of England | &0000000000341367.000000341,367 | &0000000000000839.000000839 sq mi (&0000000000002173.0000002,173 km2) |  |
| Orleans County | 073 | Albion | 1824 | Genesee County | The French Royal House of Orleans | &0000000000044171.00000044,171 | &0000000000000391.000000391 sq mi (&0000000000001013.0000001,013 km2) |  |
| Oswego County | 075 | Oswego | 1816 | Oneida County and Onondaga County | The Oswego River, from an Iroquoian word meaning "the outpouring", referring to the mouth of the river | &0000000000122377.000000122,377 | &0000000000000953.000000953 sq mi (&0000000000002468.0000002,468 km2) |  |
| Otsego County | 077 | Cooperstown | 1791 | Montgomery County | A Native American word meaning "place of the rock" | &0000000000061676.00000061,676 | &0000000000001003.0000001,003 sq mi (&0000000000002598.0000002,598 km2) |  |
| Putnam County | 079 | Carmel | 1812 | Dutchess County | Israel Putnam (1718–1790), an American Revolutionary War general | &0000000000095745.00000095,745 | &0000000000000246.000000246 sq mi (&0000000000000637.000000637 km2) |  |
| Queens County | 081 | New York City (Coextensive with Queens) | 1683 | One of 12 original counties created in the New York colony | Catherine of Braganza (1638–1705), Queen of England and wife of King Charles II of England | &0000000002229379.0000002,229,379 | &0000000000000178.280000178.28 sq mi (&0000000000000462.000000462 km2) |  |
| Rensselaer County | 083 | Troy | 1791 | Albany County | In honor of the family of Kiliaen van Rensselaer (before 1596 – after 1643), the early landholder in the Dutch New Amsterdam colony | &0000000000152538.000000152,538 | &0000000000000665.000000665 sq mi (&0000000000001722.0000001,722 km2) |  |
| Richmond County | 085 | New York City (Coextensive with Staten Island) | 1683 | One of 12 original counties created in the New York colony | Charles Lennox, 1st Duke of Richmond (1672–1723), the illegitimate son of King Charles II of England | &0000000000443728.000000443,728 | &0000000000000102.500000102.5 sq mi (&0000000000000265.000000265 km2) |  |
| Rockland County | 087 | New City | 1798 | Orange County | Early settlers' description of terrain as "rocky land" | &0000000000286753.000000286,753 | &0000000000000199.000000199 sq mi (&0000000000000515.000000515 km2) |  |
| St. Lawrence County | 089 | Canton | 1802 | Clinton County, Herkimer County, and Montgomery County | The St Lawrence River, which forms the northern border of the county and New York State | &0000000000111931.000000111,931 | &0000000000002821.0000002,821 sq mi (&0000000000007306.0000007,306 km2) |  |
| Saratoga County | 091 | Ballston Spa | 1791 | Albany County | A corruption of a Native American word meaning "the hill beside the river" | &0000000000200635.000000200,635 | &0000000000000844.000000844 sq mi (&0000000000002186.0000002,186 km2) |  |
| Schenectady County | 093 | Schenectady | 1809 | Albany County | A Mohawk word meaning "on the other side of the pine lands" | &0000000000146555.000000146,555 | &0000000000000210.000000210 sq mi (&0000000000000544.000000544 km2) |  |
| Schoharie County | 095 | Schoharie | 1795 | Albany County and Otsego County | A Mohawk word meaning "floating driftwood" | &0000000000031582.00000031,582 | &0000000000000626.000000626 sq mi (&0000000000001621.0000001,621 km2) |  |
| Schuyler County | 097 | Watkins Glen | 1854 | Chemung County, Steuben County, and Tompkins County | Philip Schuyler (1733–1804), the American Revolutionary War general and Senator from New York | &0000000000019224.00000019,224 | &0000000000000342.000000342 sq mi (&0000000000000886.000000886 km2) |  |
| Seneca County | 099 | Ovid and Waterloo | 1804 | Cayuga County | The Seneca tribe of Native Americans | &0000000000033342.00000033,342 | &0000000000000325.000000325 sq mi (&0000000000000842.000000842 km2) |  |
| Steuben County | 101 | Bath | 1796 | Ontario County | Friedrich Wilhelm von Steuben (1730–1794), the Prussian general who assisted the Continental Army during the American Revolutionary War | &0000000000098726.00000098,726 | &0000000000001404.0000001,404 sq mi (&0000000000003636.0000003,636 km2) |  |
| Suffolk County | 103 | Riverhead | 1683 | One of 12 original counties created in the New York colony | The county of Suffolk in England | &0000000001419369.0000001,419,369 | &0000000000000912.000000912 sq mi (&0000000000002362.0000002,362 km2) |  |
| Sullivan County | 105 | Monticello | 1809 | Ulster County | John Sullivan (1740–1795), an American Revolutionary War general | &0000000000073966.00000073,966 | &0000000000000997.000000997 sq mi (&0000000000002582.0000002,582 km2) |  |
| Tioga County | 107 | Owego | 1791 | Montgomery County | A Native American word meaning "at the forks," describing a meeting place | &0000000000051784.00000051,784 | &0000000000000523.000000523 sq mi (&0000000000001355.0000001,355 km2) |  |
| Tompkins County | 109 | Ithaca | 1817 | Cayuga County and Seneca County | Daniel D. Tompkins (1774–1825), the 6th Vice President of the United States | &0000000000096501.00000096,501 | &0000000000000476.000000476 sq mi (&0000000000001233.0000001,233 km2) |  |
| Ulster County | 111 | Kingston | 1683 | One of 12 original counties created in the New York colony | The Irish province of Ulster, then an earldom of the Duke of York, later King James II of England | &0000000000177749.000000177,749 | &0000000000001161.0000001,161 sq mi (&0000000000003007.0000003,007 km2) |  |
| Warren County | 113 | Queensbury | 1813 | Washington County | Joseph Warren (1741–1775), the early American patriot and American Revolutionary War general | &0000000000063303.00000063,303 | &0000000000000870.000000870 sq mi (&0000000000002253.0000002,253 km2) |  |
| Washington County | 115 | Fort Edward | 1772 | Albany County | Originally Charlotte County, renamed in 1784 after George Washington (1732–1799), the American Revolutionary War general and first President of the United States | &0000000000061042.00000061,042 | &0000000000000846.000000846 sq mi (&0000000000002191.0000002,191 km2) |  |
| Wayne County | 117 | Lyons | 1823 | Ontario County and Seneca County | General Anthony Wayne (1745–1796), the American Revolutionary War general | &0000000000093765.00000093,765 | &0000000000000604.000000604 sq mi (&0000000000001564.0000001,564 km2) |  |
| Westchester County | 119 | White Plains | 1683 | One of 12 original counties created in the New York colony | The city of Chester in England | &0000000000923459.000000923,459 | &0000000000000500.000000500 sq mi (&0000000000001295.0000001,295 km2) |  |
| Wyoming County | 121 | Warsaw | 1841 | Genesee County | A modification of a word from the Lenape language meaning "broad bottom lands" | &0000000000043424.00000043,424 | &0000000000000596.000000596 sq mi (&0000000000001544.0000001,544 km2) |  |
| Yates County | 123 | Penn Yan | 1823 | Ontario County and Steuben County | Joseph C. Yates (1768–1837), eighth Governor of New York | &0000000000024621.00000024,621 | &0000000000000376.000000376 sq mi (&0000000000000974.000000974 km2) |  |