
Below is a list of current county civil divisions, including class 2 township and borough incorporation dates. Remember that these are civil incorporation, not founding, dates.
| Name | Type | Incorporated | From |
|---|---|---|---|
| Buffalo | township | 9 April 1772 | Original while part of Northumberland County |
| East Buffalo | township | Jan 1792 | Buffalo Township, while part of Northumberland County |
| Gregg | township | 21 Mar 1865 | Brady Township, Lycoming County |
| Hartleton | borough | 18 Sep 1858 | Hartley Township |
| Hartley | township | 11 Apr 1811 | Buffalo Township, while part of Northumberland County |
| Kelly | township | 1824 | White Deer Township |
| Lewis | township | 14 Feb 1857 | Hartley Township |
| Lewisburg | borough | 31 Mar 1812 | East Buffalo Township, while part of Northumberland County |
| Limestone | township | 26 Feb 1850 | West Buffalo Township |
| Mifflinburg | borough | 14 Apr 1827 | Buffalo Township |
| New Berlin | borough | 16 May 1837 | Buffalo Township |
| Union | township | Sep 1815 | East Buffalo Township |
| West Buffalo | township | Jan 1793 | Buffalo Township, while part of Northumberland County |
| White Deer | township | Feb 1776 | Buffalo Township, while part of Northumberland County |