County facts · Land area · October 21, 2026
Largest Counties in Pennsylvania by Area and Population
The largest Pennsylvania counties by land area and by 2023 population, plus the smallest, county seats and a link to each official parcel map.
Looking for the largest counties in Pennsylvania? Pennsylvania has 67 counties covering about 44,742 square miles of land, based on the Census Bureau's 2020 Gazetteer. The largest by land area is Lycoming County, at about 1,229 square miles, roughly 9.4 times the size of the smallest, Montour County (130 sq mi). Measured by people instead, the largest is Philadelphia County, with about 1,550,542 residents in the Census Bureau's July 1, 2023 estimate.
The tables below rank the counties both ways. Each row links to the county's Platbookmapper page and straight to its official parcel viewer.
Pennsylvania counties at a glance
- Counties: 67
- Land area: about 44,742 sq mi, plus about 1,312 sq mi of water inside county lines
- Residents, 2023 estimates: about 12,961,683, or about 290 people per square mile of land
- Median county land area: about 653 sq mi
- With a verified public parcel viewer in our directory: 65 of 67 (13 of them through a statewide viewer)
The 10 largest Pennsylvania counties by land area
| # | County | Seat | Land (sq mi) | 2023 pop. | People per sq mi | Parcel viewer |
|---|---|---|---|---|---|---|
| 1 | Lycoming County | Williamsport | 1,229 | 112,724 | 92 | ArcGIS Web AppBuilder |
| 2 | Bradford County | Towanda | 1,147 | 59,695 | 52 | PASDA Pennsylvania Tax Parcels viewer |
| 3 | Clearfield County | Clearfield | 1,145 | 77,090 | 67 | ArcGIS Web AppBuilder |
| 4 | Tioga County | Wellsboro | 1,134 | 40,840 | 36 | ArcGIS Web AppBuilder |
| 5 | Centre County | Bellefonte | 1,109 | 157,795 | 142 | PASDA Pennsylvania Tax Parcels viewer |
| 6 | Potter County | Coudersport | 1,081 | 15,999 | 15 | ArcGIS Web AppBuilder |
| 7 | Somerset County | Somerset | 1,075 | 72,197 | 67 | ArcGIS Web AppBuilder |
| 8 | Westmoreland County | Greensburg | 1,028 | 351,163 | 342 | county web map |
| 9 | Crawford County | Meadville | 1,012 | 82,001 | 81 | CivQuest |
| 10 | Bedford County | Bedford | 1,012 | 47,350 | 47 | ArcGIS Web AppBuilder |
Together these 10 cover about 25% of Pennsylvania's land area and hold about 8% of its residents.
The 10 most populous Pennsylvania counties
| # | County | Seat | 2023 pop. | Land (sq mi) | Parcel viewer |
|---|---|---|---|---|---|
| 1 | Philadelphia County | Philadelphia | 1,550,542 | 134 | county web map |
| 2 | Allegheny County | Pittsburgh | 1,224,825 | 730 | ArcGIS Experience Builder |
| 3 | Montgomery County | Norristown | 868,742 | 483 | county web map |
| 4 | Bucks County | Doylestown | 645,984 | 604 | ArcGIS Web AppBuilder |
| 5 | Delaware County | Media | 576,720 | 184 | county web map |
| 6 | Lancaster County | Lancaster | 558,589 | 944 | ArcGIS Web AppBuilder |
| 7 | Chester County | West Chester | 549,784 | 751 | county web map |
| 8 | York County | York | 464,640 | 904 | ArcGIS Experience Builder |
| 9 | Berks County | Reading | 432,821 | 856 | PASDA Pennsylvania Tax Parcels viewer |
| 10 | Lehigh County | Allentown | 377,754 | 345 | ArcGIS Web AppBuilder |
These 10 hold about 56% of Pennsylvania's residents in the 2023 estimates.
The 5 smallest Pennsylvania counties by land area
| County | Seat | Land (sq mi) | 2023 pop. | Parcel viewer |
|---|---|---|---|---|
| Montour County | Danville | 130 | 17,860 | PASDA Pennsylvania Tax Parcels viewer |
| Philadelphia County | Philadelphia | 134 | 1,550,542 | county web map |
| Delaware County | Media | 184 | 576,720 | county web map |
| Union County | Lewisburg | 316 | 42,042 | PASDA Pennsylvania Tax Parcels viewer |
| Snyder County | Middleburg | 329 | 39,717 | PASDA Pennsylvania Tax Parcels viewer |
Most and least crowded
- Most people per square mile: Philadelphia County, about 11,541 (then Delaware County, 3,138, and Montgomery County, 1,799)
- Fewest people per square mile: Cameron County, about 11 (then Sullivan County, 13, and Potter County, 15)
Counties with the most water
The Census Bureau reports water separately from land. It counts lakes, reservoirs, rivers and, for coastal and Great Lakes counties, the water inside the county boundary.
- Erie County: about 759 sq mi of water, 49% of its total area
- Lancaster County: about 40 sq mi of water, 4% of its total area
- Dauphin County: about 33 sq mi of water, 6% of its total area
Using these numbers in a land search
- Land area is not parcel count. A large rural county can hold fewer parcels than a small suburban one, so size alone says little about how busy its parcel map is.
- Search, don't scroll. In a big county, type an address, owner name or parcel number into the viewer's search box, where it has one, instead of panning across the map.
- Records follow the county line. Deeds, plats and tax bills are kept by the county where the parcel sits, so a tract that crosses a county line usually has a parcel number in each county.
- Rounded figures. Land and water areas are rounded to whole square miles. People per square mile is the 2023 estimate divided by land area.
Related guides
- Pennsylvania county GIS websites by viewer
- Pennsylvania plat maps
- Pennsylvania landowner maps for hunting
- Maryland–Pennsylvania border counties
- New Jersey–Pennsylvania border counties
- New York–Pennsylvania border counties
More: All Pennsylvania counties on Platbookmapper
Sources
- U.S. Census Bureau Gazetteer files, 2020 county land and water area.
- U.S. Census Bureau, Population Estimates Program, county totals, Vintage 2023 (July 1, 2023 estimates)
- Platbookmapper county GIS directory (live data file behind our county pages, pulled October 21, 2026) for each county's official parcel viewer.
- County seats: Wikidata (county seat property), cross-checked against Census place names.