County outline
Where Juniata County is located
Area breakdown
Land accounts for 99.5% of Juniata County’s measured area and water for 0.5%. Its combined area converts to 1,019.2 square kilometers or approximately 251,850 acres.
Green: land · blue: water
| Measurement | Square miles | Square kilometers | Acres |
|---|---|---|---|
| Land | 391.391 | 1,013.698 | 250,490.2 |
| Water | 2.125 | 5.504 | 1,360 |
| Total | 393.516 | 1,019.202 | 251,850.2 |
How Juniata County compares
By original Census land area, Juniata County ranks #57 of 67 in Pennsylvania and #2568 of 3,222 nationally. National rankings include the 50 states, District of Columbia, and Puerto Rico.
Its land area is 0.599 times the Pennsylvania county-equivalent median of 653.3 square miles. It accounts for 0.9% of the combined county land area in the state.
See the complete Pennsylvania ranking · What counts as a county equivalent?
Population and density of Juniata County
The Census Bureau estimates that 23,403 people lived in Juniata County on July 1, 2025. That ranks #1,722 of 3,222 county equivalents nationally and #61 of 67 in Pennsylvania. Since the April 1, 2020 estimates base of 23,500, the population has declined by 97 (−0.4%), compared with +0.4% for Pennsylvania as a whole.
With 391.4 square miles of land, that is 60 people per square mile (23 per km²), placing Juniata County #1,388 nationally for density and #52 in Pennsylvania. The median county equivalent has 47 people per square mile; the Pennsylvania median is 137. Put another way, there are about 11 acres of land per resident.
| July 1 | 2020 | 2021 | 2022 | 2023 | 2024 | 2025 |
|---|---|---|---|---|---|---|
| Estimate | 23,476 | 23,346 | 23,296 | 23,409 | 23,454 | 23,403 |
| Change | — | −130 | −50 | +113 | +45 | −51 |
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 Juniata County
Juniata County is divided into 17 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 Fayette township, with 3,337 residents (14.3% of the county). The largest by land is Lack township, at 57 mi², or 14.6% of the county’s land. The county seat, Mifflintown borough, has 819 residents. Among those with at least 1,000 residents in 2020, Walker township grew fastest since then (+0.3%).
| County subdivision | Population 2025 | Since 2020 | Land mi² | Share of county land |
|---|---|---|---|---|
| Fayette township | 3,337 | −0.1% | 39.5 | 10.1% |
| Fermanagh township | 2,861 | −0.4% | 32 | 8.2% |
| Walker township | 2,790 | +0.3% | 28.8 | 7.4% |
| Monroe township | 2,029 | −0.8% | 19.9 | 5.1% |
| Milford township | 1,962 | −1.3% | 40.1 | 10.2% |
| Delaware township | 1,622 | 0% | 29.5 | 7.5% |
| Susquehanna township | 1,199 | −0.6% | 16.5 | 4.2% |
| Tuscarora township | 1,135 | +0.1% | 47.2 | 12.1% |
| Turbett township | 969 | −0.8% | 16.4 | 4.2% |
| Mifflintown boroughCounty seat | 819 | −2.6% | 0.14 | 0% |
| Port Royal borough | 797 | −2.2% | 0.602 | 0.2% |
| Spruce Hill township | 793 | +0.6% | 21.8 | 5.6% |
| Beale township | 783 | +1.6% | 21.9 | 5.6% |
| Thompsontown borough | 628 | +1.1% | 0.326 | 0.1% |
| Lack township | 625 | −1.9% | 57 | 14.6% |
Show the other 2 subdivisions
| Name | Population 2025 | Since 2020 | Land mi² |
|---|---|---|---|
| Greenwood township | 539 | +1.5% | 19.5 |
| Mifflin borough | 515 | −2.6% | 0.174 |
Population: U.S. Census Bureau Vintage 2025 subcounty estimates, counting only the part of each subdivision inside Juniata County. Land: 2026 Census Gazetteer. How communities are listed.
Metropolitan area
Juniata County is not part of any metropolitan or micropolitan statistical area in the Office of Management and Budget’s July 2023 delineation; 1,306 other county equivalents are also outside one. These areas are built around an urban core of at least 10,000 people plus the counties tied to it by commuting, so counties outside them are generally rural.
ZIP codes
15 ZIP Code Tabulation Areas have land in Juniata County; 10 of them have most of their land inside the county, and the others mainly cover neighboring areas.
170141702117035170451704917056170581705917062170761708217086170941724317853
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 Juniata County
Juniata County shares a land border with 6 county equivalents. It has more land than 1 of them. The largest neighbor is Huntingdon County (874.6 mi²) and the smallest is Snyder County (328.8 mi²). Together with its neighbors, Juniata County forms a block of 3,787.2 mi² of land, of which it holds 10.3%.
| Bordering county equivalent | Land mi² | Size vs. Juniata | Compare |
|---|---|---|---|
| Huntingdon County | 874.6 | 2.2× larger | Compare |
| Franklin County | 772.3 | 2× larger | Compare |
| Perry County | 551.5 | 1.4× larger | Compare |
| Northumberland County | 457.7 | 1.2× larger | Compare |
| Mifflin County | 411 | 1.1× larger | Compare |
| Snyder County | 328.8 | 1.2× smaller | Compare |
How big is Juniata County compared with U.S. states?
Juniata County has less land than any of the 50 states. Rhode Island, the smallest state by land area, has 1,033.9 mi², about 2.6 times as much. Pennsylvania’s county land could hold about 114 areas the size of Juniata County.
Another way to picture it: the same land area would fill a square about 19.8 miles (31.8 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 Juniata County?
Juniata County has more land than 654 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 Juniata County at #2,628 nationally by total area, 60 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 0.5%, compared with a national county-equivalent median of 1.2% — 0.6 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 Juniata County in the national ranking. They can be in different states and are not necessarily geographic neighbors.
| Land rank | County equivalent | Land mi² | Comparison |
|---|---|---|---|
| #2567 | Cole County, Missouri | 391.6 | Compare |
| #2568 | Juniata County, Pennsylvania | 391.4 | This county |
| #2569 | Talbot County, Georgia | 391.4 | 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 40.530673, -77.400438. 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: 1,013,697,483 m²; AWATER: 5,502,985 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 Juniata County?
Juniata County, Pennsylvania has 391.4 square miles (1,013.7 km²) of land and 2.125 square miles of water, for a total area of 393.5 square miles. It ranks #2568 of 3,222 U.S. county equivalents by land area.
Is Juniata County the largest county in Pennsylvania?
No. Juniata County ranks #57 of 67 in Pennsylvania by land area. The largest is Lycoming County, with 1,228.9 square miles of land.
What counties border Juniata County?
Juniata County shares a land border with Perry County, Mifflin County, Snyder County, Huntingdon County, Franklin County, and Northumberland County.
What is the population of Juniata County?
The Census Bureau estimates Juniata County had 23,403 residents on July 1, 2025, ranking #1,722 of 3,222 county equivalents. That is 60 people per square mile of land.
What is the county seat of Juniata County?
The county seat of Juniata County is Mifflintown.
What cities and towns are in Juniata County?
Juniata County has 17 county subdivisions (cities, towns and townships). The most populous five are Fayette township, Fermanagh township, Walker township, Monroe township, and Milford township.
Is Juniata County part of a metropolitan area?
No. Juniata County is outside every metropolitan and micropolitan statistical area in the July 2023 OMB delineation.
How many ZIP codes are in Juniata County?
15 ZIP Code Tabulation Areas have land in Juniata County, and 10 of them have most of their land inside the county. Census ZIP Code Tabulation Areas approximate USPS ZIP Code areas.
How does Juniata County compare with U.S. states?
It has less land than every state. Rhode Island, the smallest, has 2.6 times as much land.
How many acres of land are in Juniata County?
The land measurement converts to approximately 250,490 acres. Including water, total area is approximately 251,850 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.