Founded in 1804, Jefferson County is one of 67 counties in the state of Pennsylvania. Historically, Jefferson County was formed from parts of Lycoming County Attached to Westmoreland County until 1806 and to Indiana County until 1830. The city of Brookville is the county seat. With FIPS code of 65, Jefferson County has a population of 44,114 and area of 657 square miles (1,702 km2).
List of all cities in Jefferson County, PA alphabetically
| City/Town | Postal Code | Area Code |
| Anita, PA | 15711 | 814 |
| Big Run, PA | 15715 | 814 |
| Brockway, PA | 15824 | 814 |
| Brookville, PA | 15825 | 814 |
| Coolspring, PA | 15730 | 814 |
| Corsica, PA | 15829 | 814 |
| De Lancey, PA | 15733 | 814 |
| Falls Creek, PA | 15840 | 814 |
| Frostburg, PA | 15740 | 814 |
| Hallton, PA | 15860 | 814 |
| Hamilton, PA | 15744 | 814 |
| Hazen, PA | 15825 | 814 |
| Juneau, PA | 15767 | 814 |
| Knox Dale, PA | 15847 | 814 |
| Oliveburg, PA | 15764 | 814 |
| Punxsutawney, PA | 15767 | 814 |
| Reynoldsville, PA | 15851 | 814 |
| Ringgold, PA | 15770 | 814 |
| Sigel, PA | 15860 | 814 |
| Sprankle Mills, PA | 15776 | 814 |
| Stump Creek, PA | 15863 | 814 |
| Summerville, PA | 15864 | 814 |
| Sykesville, PA | 15865 | 814 |
| Timblin, PA | 15778 | 814 |
| Valier, PA | 15780 | 814 |
| Walston, PA | 15781 | 814 |
| Worthville, PA | 15784 | 814 |