Pennsylvania Counties, Demographics & Geography
Complete official guide to all 67 counties in Pennsylvania (PA). Explore 2024 US Census population estimates, county seats, FIPS codes, land areas, and interactive mapping tools powered by GeoMap Suite.
Pennsylvania County Breakdown
Showing 14 of 14 documented counties and seats.
County Name | FIPS | County Seat | Population (Census) | Land Area | Quick Tool |
|---|---|---|---|---|---|
| Philadelphia County | 42101 | Philadelphia | 1,550,542 | 134 sq mi | Lookup |
| Allegheny County (Pittsburgh) | 42003 | Pittsburgh | 1,250,578 | 730 sq mi | Lookup |
| Montgomery County | 42091 | Norristown | 856,553 | 483 sq mi | Lookup |
| Bucks County | 42017 | Doylestown | 646,538 | 607 sq mi | Lookup |
| Delaware County | 42045 | Media | 576,832 | 184 sq mi | Lookup |
| Lancaster County | 42071 | Lancaster | 552,984 | 949 sq mi | Lookup |
| Chester County | 42029 | West Chester | 534,413 | 756 sq mi | Lookup |
| York County | 42133 | York | 456,438 | 905 sq mi | Lookup |
| Berks County (Reading) | 42011 | Reading | 428,849 | 859 sq mi | Lookup |
| Lehigh County (Allentown) | 42077 | Allentown | 374,557 | 345 sq mi | Lookup |
| Luzerne County (Wilkes-Barre) | 42079 | Wilkes-Barre | 325,594 | 890 sq mi | Lookup |
| Northampton County (Bethlehem/Easton) | 42095 | Easton | 313,124 | 373 sq mi | Lookup |
| Dauphin County (Harrisburg) | 42043 | Harrisburg | 286,401 | 525 sq mi | Lookup |
| Erie County | 42049 | Erie | 270,876 | 799 sq mi | Lookup |
Geographic Structure of Pennsylvania Counties
County Administration & Governance
In Pennsylvania, county governments manage vital public infrastructure, tax assessments, law enforcement, judicial courts, election administration, and public records. The county seat (Philadelphia and other municipal headquarters) houses the primary courthouse, commissioners, and sheriff’s department.
All Pennsylvania counties carry a unique 5-digit Federal Information Processing Standard (FIPS) code, where the first two digits (42) designate the state and the remaining three digits identify each specific jurisdiction.
Geographic & Demographic Highlights
- Most Populous County:Philadelphia County (1,550,542 residents)
- Largest by Land Area:Lancaster County (949 sq mi)
- State Capital:Harrisburg
- Census Bureau Region:Northeast United States
Demographic calculations derive from the United States Census Bureau 2024 Population Estimates Program (PEP) and TIGER/Line geographic boundary files.