Jefferson County, county in New York, United States. As of 2020 county had an estimated population of 108,095 inhabitants. The county was created 218 years ago in 1805. Its county seat is "Watertown".
There are 29 city/town in Jefferson County, NY. The largest city of Jefferson County is Brownville with a population of 5,876. Other cities include, Adams population 4,847, Clayton population 4,647, Watertown population 4,426, Champion population 4,236
Brownville, human settlement in Jefferson County, New York, United States of America
Adams, town in New York, United States
Clayton, village in Jefferson County, New York, United States
Cities, Towns, Neighborhoods & Other Populated Places in Jefferson County.
| City Name | Title | County | Population |
|---|---|---|---|
| Adams | Town in New York, United States | Jefferson | 4,847 |
| Adams Center | Census-designated place in Jefferson County, New York | Jefferson | 1,568 |
| Alexandria Bay | US village in New York State | Jefferson | 1,012 |
| Antwerp | Town in Jefferson County, New York, United States | Jefferson | 641 |
| Black River | Human settlement in Jefferson County, New York, United States of America | Jefferson | 1,217 |
| Brownville | Human settlement in Jefferson County, New York, United States of America | Jefferson | 5,876 |
| Calcium | Census-designated place in Jefferson County, New York | Jefferson | 3,491 |
| Cape Vincent | Town in New York | Jefferson | 2,661 |
| Carthage | Village in the United States | Jefferson | 3,256 |
| Champion | Town in Jefferson County, New York | Jefferson | 4,236 |
| Chaumont | Town | Jefferson | 568 |
| Clayton | Village in Jefferson County, New York, United States | Jefferson | 4,647 |
| Deferiet | Human settlement in Jefferson County, New York, United States of America | Jefferson | 278 |
| Dexter | Village in New York | Jefferson | 980 |
| Ellisburg | Town in Jefferson County, New York, United States | Jefferson | 3,284 |
| Evans Mills | Human settlement in Jefferson County, New York, United States of America | Jefferson | 545 |
| Glen Park | Village in Jefferson County, New York, United States | Jefferson | 462 |
| Henderson | Town in Jefferson County, New York, United States | Jefferson | 1,287 |
| Lorraine | New York town | Jefferson | 970 |
| Mannsville | Human settlement in Jefferson County, New York, United States of America | Jefferson | 330 |
| Philadelphia | Town in Jefferson County, New York, United States | Jefferson | 1,759 |
| Rodman | Human settlement in United States of America | Jefferson | 1,109 |
| Sackets Harbor | City in Jefferson County, New York, United States of America | Jefferson | 1,376 |
| Smithville | Town in New York, United States | Jefferson | 1,257 |
| Theresa | Town in Jefferson County, New York, United States | Jefferson | 766 |
| Watertown | Town in Jefferson County, New York | Jefferson | 4,426 |
| Waterville | Village in New York, United States | Jefferson | 1,502 |
| West Carthage | Village in New York, USA | Jefferson | 1,901 |
| Worth | Human settlement in Jefferson County, New York, United States of America | Jefferson | 219 |
