County outline
Where Cumberland County is located
Area breakdown
Land accounts for 99.1% of Cumberland County’s measured area and water for 0.9%. Its combined area converts to 1,425.5 square kilometers or approximately 352,239 acres.
Green: land · blue: water
| Measurement | Square miles | Square kilometers | Acres |
|---|---|---|---|
| Land | 545.483 | 1,412.794 | 349,109.1 |
| Water | 4.89 | 12.665 | 3,129.6 |
| Total | 550.373 | 1,425.46 | 352,238.7 |
How Cumberland County compares
By original Census land area, Cumberland County ranks #41 of 67 in Pennsylvania and #1911 of 3,222 nationally. National rankings include the 50 states, District of Columbia, and Puerto Rico.
Its land area is 0.835 times the Pennsylvania county-equivalent median of 653.3 square miles. It accounts for 1.2% of the combined county land area in the state.
See the complete Pennsylvania ranking · What counts as a county equivalent?
Population and density of Cumberland County
The Census Bureau estimates that 277,270 people lived in Cumberland County on July 1, 2025. That ranks #268 of 3,222 county equivalents nationally and #15 of 67 in Pennsylvania. Since the April 1, 2020 estimates base of 259,461, the population has grown by 17,809 (+6.9%), compared with +0.4% for Pennsylvania as a whole.
With 545.5 square miles of land, that is 508 people per square mile (196 per km²), placing Cumberland County #336 nationally for density and #13 in Pennsylvania. The median county equivalent has 47 people per square mile; the Pennsylvania median is 137. Put another way, there are about 1.3 acres of land per resident.
| July 1 | 2020 | 2021 | 2022 | 2023 | 2024 | 2025 |
|---|---|---|---|---|---|---|
| Estimate | 260,251 | 265,577 | 268,588 | 271,177 | 274,656 | 277,270 |
| Change | — | +5,326 | +3,011 | +2,589 | +3,479 | +2,614 |
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 Cumberland County
Cumberland County is divided into 33 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 Hampden township, with 35,401 residents (12.8% of the county). The largest by land is Southampton township, at 51.4 mi², or 9.4% of the county’s land. The county seat, Carlisle borough, has 22,693 residents. Among those with at least 1,000 residents in 2020, Southampton township grew fastest since then (+14.5%).
| County subdivision | Population 2025 | Since 2020 | Land mi² | Share of county land |
|---|---|---|---|---|
| Hampden township | 35,401 | +8.1% | 17.3 | 3.2% |
| Upper Allen township | 24,700 | +6.2% | 13.2 | 2.4% |
| Carlisle boroughCounty seat | 22,693 | +12.8% | 5.533 | 1% |
| Silver Spring township | 21,670 | +11% | 32.3 | 5.9% |
| East Pennsboro township | 21,658 | +3.6% | 10.5 | 1.9% |
| Lower Allen township | 21,254 | +5.9% | 10.1 | 1.8% |
| South Middleton township | 17,792 | +10.2% | 48.8 | 8.9% |
| North Middleton township | 13,031 | +7.8% | 23.2 | 4.3% |
| Mechanicsburg borough | 10,037 | +8.3% | 2.41 | 0.4% |
| Southampton township | 8,523 | +14.5% | 51.4 | 9.4% |
| Camp Hill borough | 8,199 | +1% | 2.125 | 0.4% |
| Middlesex township | 7,636 | +9.7% | 25.7 | 4.7% |
| New Cumberland borough | 7,590 | +0.8% | 1.675 | 0.3% |
| Monroe township | 6,748 | +8.5% | 26.1 | 4.8% |
| West Pennsboro township | 5,699 | +2% | 30.2 | 5.5% |
Show the other 18 subdivisions
| Name | Population 2025 | Since 2020 | Land mi² |
|---|---|---|---|
| Dickinson township | 5,519 | +4.1% | 45.8 |
| Lemoyne borough | 4,801 | +2.6% | 1.612 |
| Shippensburg borough | 4,434 | +2.9% | 1.311 |
| Shippensburg township | 4,343 | +0.9% | 2.481 |
| Wormleysburg borough | 3,078 | +1.2% | 0.777 |
| Penn township | 2,937 | +2.3% | 29.6 |
| North Newton township | 2,600 | +2.1% | 22.8 |
| Hopewell township | 2,559 | +3% | 27.7 |
| Upper Frankford township | 2,309 | +8.3% | 19.4 |
| Mount Holly Springs borough | 2,019 | +1.3% | 1.36 |
| Lower Frankford township | 1,833 | +4.8% | 14.7 |
| Lower Mifflin township | 1,795 | +2.3% | 23.8 |
| Shiremanstown borough | 1,657 | +0.9% | 0.306 |
| Newville borough | 1,409 | +1.1% | 0.419 |
| South Newton township | 1,393 | +1.5% | 11.3 |
| Upper Mifflin township | 1,381 | +4.1% | 21.7 |
| Newburg borough | 359 | +1.7% | 0.185 |
| Cooke township | 213 | +2.4% | 19.8 |
Population: U.S. Census Bureau Vintage 2025 subcounty estimates, counting only the part of each subdivision inside Cumberland County. Land: 2026 Census Gazetteer. How communities are listed.
Metropolitan area
Cumberland County is a central county of the Harrisburg-Carlisle, PA Metropolitan Statistical Area. Its 3 county equivalents have 617,427 residents on 1,621.8 square miles of land; Cumberland County accounts for 33.6% of the land and 44.9% of the residents. By combined land it ranks #200 of 393 metropolitan areas, and #96 by population. It belongs to the Harrisburg-York-Lebanon, PA Combined Statistical Area.
| County equivalent | Population 2025 | Land mi² |
|---|---|---|
| Dauphin County | 293,351 | 524.9 |
| Cumberland County | 277,270 | 545.5 |
| Perry County | 46,806 | 551.5 |
ZIP codes
21 ZIP Code Tabulation Areas have land in Cumberland County; 17 of them have most of their land inside the county, and the others mainly cover neighboring areas.
170071701117013170151701917025170271704317050170531705517065170701708117093172401724117257172661730717324
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 Cumberland County
Cumberland County shares a land border with 5 county equivalents. It has more land than 2 of them. The largest neighbor is York County (904.4 mi²) and the smallest is Adams County (518.6 mi²). Together with its neighbors, Cumberland County forms a block of 3,817 mi² of land, of which it holds 14.3%.
| Bordering county equivalent | Land mi² | Size vs. Cumberland | Compare |
|---|---|---|---|
| York County | 904.4 | 1.7× larger | Compare |
| Franklin County | 772.3 | 1.4× larger | Compare |
| Perry County | 551.5 | about the same | Compare |
| Dauphin County | 524.9 | about the same | Compare |
| Adams County | 518.6 | 1.1× smaller | Compare |
How big is Cumberland County compared with U.S. states?
Cumberland County has less land than any of the 50 states. Rhode Island, the smallest state by land area, has 1,033.9 mi², about 1.9 times as much. Pennsylvania’s county land could hold about 82 areas the size of Cumberland County.
Another way to picture it: the same land area would fill a square about 23.4 miles (37.6 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 Cumberland County?
Cumberland County has more land than 1,311 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 Cumberland County at #2,005 nationally by total area, 94 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 0.9%, compared with a national county-equivalent median of 1.2% — 0.3 percentage points lower. 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 Cumberland County in the national ranking. They can be in different states and are not necessarily geographic neighbors.
| Land rank | County equivalent | Land mi² | Comparison |
|---|---|---|---|
| #1910 | Hall County, Nebraska | 546.5 | Compare |
| #1911 | Cumberland County, Pennsylvania | 545.5 | This county |
| #1912 | Franklin County, Florida | 545 | Compare |
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.
Representative coordinates
The Census internal point is 40.164805, -77.263442. It represents a location inside the geography; it is not necessarily the centroid or the address of a courthouse.
Source and precision
U.S. Census Bureau, 2026 Gazetteer Files, Counties. Original ALAND: 1,412,794,386 m²; AWATER: 12,664,175 m². Rankings use ALAND; exact ties use ascending GEOID. Tables preserve Census-published square miles to three decimals, with conversions based on those values.
Common questions
How big is Cumberland County?
Cumberland County, Pennsylvania has 545.5 square miles (1,412.8 km²) of land and 4.89 square miles of water, for a total area of 550.4 square miles. It ranks #1911 of 3,222 U.S. county equivalents by land area.
Is Cumberland County the largest county in Pennsylvania?
No. Cumberland County ranks #41 of 67 in Pennsylvania by land area. The largest is Lycoming County, with 1,228.9 square miles of land.
What counties border Cumberland County?
Cumberland County shares a land border with Perry County, Adams County, Franklin County, York County, and Dauphin County.
What is the population of Cumberland County?
The Census Bureau estimates Cumberland County had 277,270 residents on July 1, 2025, ranking #268 of 3,222 county equivalents. That is 508 people per square mile of land.
What is the county seat of Cumberland County?
The county seat of Cumberland County is Carlisle.
What cities and towns are in Cumberland County?
Cumberland County has 33 county subdivisions (cities, towns and townships). The most populous five are Hampden township, Upper Allen township, Carlisle borough, Silver Spring township, and East Pennsboro township.
Is Cumberland County part of a metropolitan area?
Yes. It is a central county of the Harrisburg-Carlisle, PA Metropolitan Statistical Area, which has 3 county equivalents and 617,427 residents.
How many ZIP codes are in Cumberland County?
21 ZIP Code Tabulation Areas have land in Cumberland County, and 17 of them have most of their land inside the county. Census ZIP Code Tabulation Areas approximate USPS ZIP Code areas.
How does Cumberland County compare with U.S. states?
It has less land than every state. Rhode Island, the smallest, has 1.9 times as much land.
How many acres of land are in Cumberland County?
The land measurement converts to approximately 349,109 acres. Including water, total area is approximately 352,239 acres. One square mile equals 640 acres.
Why might another source show a different area?
Check whether it reports land or total area, its Census vintage, and its rounding. Our guide explains how to reconcile county area figures.
Can this establish a property boundary?
No. Statistical measurements and generalized maps do not establish property lines. Consult the relevant local surveying or land-records authority.