Chester County area

Population and density of Chester County

The Census Bureau estimates that 557,116 people lived in Chester County on July 1, 2025. That ranks #131 of 3,222 county equivalents nationally and #7 of 67 in Pennsylvania. Since the April 1, 2020 estimates base of 534,429, the population has grown by 22,687 (+4.2%), compared with +0.4% for Pennsylvania as a whole.

With 750.6 square miles of land, that is 742 people per square mile (287 per km²), placing Chester County #249 nationally for density and #8 in Pennsylvania. The median county equivalent has 47 people per square mile; the Pennsylvania median is 137. Put another way, there are about 0.862 acres of land per resident.

U.S. Census Bureau, Vintage 2025 population estimates. Estimates are revised each year and are not decennial census counts. Density divides the whole population by the whole county’s land area, so it describes an average, not how settlement is distributed within the county. Population sources and methods.

Cities and towns in Chester County

Chester County is divided into 73 municipalities and townships. In Pennsylvania, county subdivisions are local governments, and together they cover all of the county’s land and residents.

The most populous is Tredyffrin township, with 31,818 residents (5.7% of the county). The largest by land is Honey Brook township, at 24.8 mi², or 3.3% of the county’s land. The county seat, West Chester borough, has 19,591 residents. Among those with at least 1,000 residents in 2020, Kennett Square borough grew fastest since then (+16%).

Population: U.S. Census Bureau Vintage 2025 subcounty estimates, counting only the part of each subdivision inside Chester County. Land: 2026 Census Gazetteer. How communities are listed.

Metropolitan area

Chester County is a central county of the Philadelphia-Camden-Wilmington, PA-NJ-DE-MD Metropolitan Statistical Area, in the Montgomery County-Bucks County-Chester County, PA metropolitan division. Its 11 county equivalents have 6,329,118 residents on 4,603.2 square miles of land; Chester County accounts for 16.3% of the land and 8.8% of the residents. By combined land it ranks #58 of 393 metropolitan areas, and #9 by population. It belongs to the Philadelphia-Reading-Camden, PA-NJ-DE-MD Combined Statistical Area.

ZIP codes

46 ZIP Code Tabulation Areas have land in Chester County; 38 of them have most of their land inside the county, and the others mainly cover neighboring areas.

17527175551907319087193011931019311193121931619317193191932019330193331933519341193421934319344193451934819350193521935519358193621936319365193671936919372193731937419375193801938219383193901942519442194571946019465194751952019543

ZIP Code Tabulation Areas are the Census Bureau’s approximations of USPS ZIP Code service areas, from the 2020 Census relationship files. Lighter codes have less than half of their land in this county. Post-office-box and single-address ZIP Codes have no tabulation area.

Counties bordering Chester County

Chester County shares a land border with 6 county equivalents, including 2 in Maryland and Delaware. It has more land than 4 of them. The largest neighbor is Lancaster County (943.9 mi²) and the smallest is Delaware County (183.8 mi²). Together with its neighbors, Chester County forms a block of 3,990.3 mi² of land, of which it holds 18.8%.

How big is Chester County compared with U.S. states?

Chester County has less land than any of the 50 states. Rhode Island, the smallest state by land area, has 1,033.9 mi², about 1.4 times as much. Pennsylvania’s county land could hold about 60 areas the size of Chester County.

Another way to picture it: the same land area would fill a square about 27.4 miles (44.1 km) on each side. Real county shapes are rarely square, so this is a scale reference rather than a width or driving distance.

State figures are the sums of each state’s county-equivalent land measurements in the same Census release, so states and counties are compared on the same basis. Published state totals can differ slightly because of rounding. Compare all states · Counties bigger than entire states.

What stands out about Chester County?

Chester County has more land than 2,047 of the other 3,221 county equivalents in the dataset.

A median is the middle county-equivalent measurement, not the average of the largest and smallest. All three bars use the same linear scale. Very small areas may appear as a thin sliver; the labels retain their values.

Does including water change its rank?

Using land plus water places Chester County at #1,267 nationally by total area, 92 places farther from the top than its land rank. Other county equivalents gain more area when their water measurements are included.

Its water share is 1.1%, compared with a national county-equivalent median of 1.2%. The two percentages are within 0.1 percentage points of each other. This describes the statistical geography’s land/water mix, not flood exposure or developable land.

Closest positions in the national land ranking

These entries sit immediately beside Chester County in the national ranking. They can be in different states and are not necessarily geographic neighbors.

Calculated from the same Census release as the area table. Total-area order uses original ALAND + AWATER; water shares and chart labels use published square miles. Calculation details.