County outline
Where Pike County is located
Area breakdown
Land accounts for 97.9% of Pike County’s measured area and water for 2.1%. Its combined area converts to 2,198.4 square kilometers or approximately 543,247 acres.
Green: land · blue: water
| Measurement | Square miles | Square kilometers | Acres |
|---|---|---|---|
| Land | 831.352 | 2,153.192 | 532,065.3 |
| Water | 17.472 | 45.252 | 11,182.1 |
| Total | 848.824 | 2,198.444 | 543,247.4 |
How Pike County compares
By original Census land area, Pike County ranks #14 of 102 in Illinois and #1014 of 3,222 nationally. National rankings include the 50 states, District of Columbia, and Puerto Rico.
Its land area is 1.628 times the Illinois county-equivalent median of 510.7 square miles. It accounts for 1.5% of the combined county land area in the state.
See the complete Illinois ranking · What counts as a county equivalent?
Population and density of Pike County
The Census Bureau estimates that 14,231 people lived in Pike County on July 1, 2025. That ranks #2,213 of 3,222 county equivalents nationally and #73 of 102 in Illinois. Since the April 1, 2020 estimates base of 14,728, the population has declined by 497 (−3.4%), compared with −0.8% for Illinois as a whole.
With 831.4 square miles of land, that is 17 people per square mile (6.6 per km²), placing Pike County #2,405 nationally for density and #97 in Illinois. The median county equivalent has 47 people per square mile; the Illinois median is 44. Put another way, there are about 37 acres of land per resident.
| July 1 | 2020 | 2021 | 2022 | 2023 | 2024 | 2025 |
|---|---|---|---|---|---|---|
| Estimate | 14,635 | 14,600 | 14,539 | 14,351 | 14,286 | 14,231 |
| Change | — | −35 | −61 | −188 | −65 | −55 |
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 Pike County
17 incorporated places lie at least partly in Pike County. Together they are home to 9,451 people (66.4%); the other 4,780 (33.6%) live outside any incorporated place, in unincorporated communities and rural areas.
The largest is Pittsfield city, with 4,041 residents in the county.
| Incorporated place | Population 2025 | Since 2020 | Land mi² |
|---|---|---|---|
| Pittsfield cityCounty seat | 4,041 | −3.6% | 4.782 |
| Barry city | 1,247 | −4.2% | 1.432 |
| Griggsville city | 1,047 | −4.7% | 1.106 |
| Pleasant Hill village | 895 | −2.5% | 0.765 |
| Hull village | 376 | −4.8% | 1.825 |
| New Canton town | 325 | −3% | 0.881 |
| Perry village | 302 | −3.8% | 0.386 |
| Nebo village | 270 | −2.9% | 0.434 |
| Milton village | 206 | −2.4% | 0.386 |
| Kinderhook village | 188 | −2.1% | 0.808 |
| Baylis village | 165 | −2.9% | 0.471 |
| New Salem village | 116 | −4.1% | 1.049 |
| Pearl village | 108 | −2.7% | 1.505 |
| Detroit village | 74 | −1.3% | 0.251 |
| El Dara village | 61 | −4.7% | 1.011 |
Show the other 2 places
| Name | Population 2025 | Since 2020 | Land mi² |
|---|---|---|---|
| Florence village | 17 | −5.6% | 0.276 |
| Valley City village | 13 | +8.3% | 0.27 |
Population: U.S. Census Bureau Vintage 2025 subcounty estimates, counting only the part of each place inside Pike County. Land: 2026 Census Gazetteer, for the whole place even where it extends into other counties. How communities are listed.
Metropolitan area
Pike 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
16 ZIP Code Tabulation Areas have land in Pike County; 15 of them have most of their land inside the county, and the others mainly cover neighboring areas.
62312623146232362340623436234562352623536235562356623576236162362623636236662370
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 Pike County
Pike County shares a land border with 9 county equivalents, including 3 in Missouri. It has more land than 8 of them. The largest neighbor is Adams County (855.2 mi²) and the smallest is Scott County (250.8 mi²). Together with its neighbors, Pike County forms a block of 5,186.1 mi² of land, of which it holds 16%.
| Bordering county equivalent | Land mi² | Size vs. Pike | Compare |
|---|---|---|---|
| Adams County | 855.2 | about the same | Compare |
| Pike CountyMissouri | 670.4 | 1.2× smaller | Compare |
| Morgan County | 569 | 1.5× smaller | Compare |
| Greene County | 543.1 | 1.5× smaller | Compare |
| Ralls CountyMissouri | 469.8 | 1.8× smaller | Compare |
| Marion CountyMissouri | 436.9 | 1.9× smaller | Compare |
| Brown County | 305.7 | 2.7× smaller | Compare |
| Calhoun County | 253.8 | 3.3× smaller | Compare |
| Scott County | 250.8 | 3.3× smaller | Compare |
How big is Pike County compared with U.S. states?
Pike County has less land than any of the 50 states. Rhode Island, the smallest state by land area, has 1,033.9 mi², about 1.2 times as much. Illinois’s county land could hold about 67 areas the size of Pike County.
Another way to picture it: the same land area would fill a square about 28.8 miles (46.4 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 Pike County?
Pike County has more land than 2,208 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 Pike County at #1,090 nationally by total area, 76 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 2.1%, compared with a national county-equivalent median of 1.2% — 0.9 percentage points higher. 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 Pike County in the national ranking. They can be in different states and are not necessarily geographic neighbors.
| Land rank | County equivalent | Land mi² | Comparison |
|---|---|---|---|
| #1013 | Avoyelles Parish, Louisiana | 831.4 | Compare |
| #1014 | Pike County, Illinois | 831.4 | This county |
| #1015 | Washington County, New York | 831.2 | 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 39.625106, -90.889034. 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: 2,153,190,727 m²; AWATER: 45,251,537 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 Pike County?
Pike County, Illinois has 831.4 square miles (2,153.2 km²) of land and 17.5 square miles of water, for a total area of 848.8 square miles. It ranks #1014 of 3,222 U.S. county equivalents by land area.
Is Pike County the largest county in Illinois?
No. Pike County ranks #14 of 102 in Illinois by land area. The largest is McLean County, with 1,183.2 square miles of land.
What counties border Pike County?
Pike County shares a land border with Adams County, Scott County, Pike County, Missouri, Brown County, Calhoun County, Greene County, Ralls County, Missouri, Marion County, Missouri, and Morgan County.
What is the population of Pike County?
The Census Bureau estimates Pike County had 14,231 residents on July 1, 2025, ranking #2,213 of 3,222 county equivalents. That is 17 people per square mile of land.
What is the county seat of Pike County?
The county seat of Pike County is Pittsfield.
What cities and towns are in Pike County?
Pike County has 17 incorporated places. The most populous five are Pittsfield city, Barry city, Griggsville city, Pleasant Hill village, and Hull village; 4,780 residents live outside any incorporated place.
Is Pike County part of a metropolitan area?
No. Pike County is outside every metropolitan and micropolitan statistical area in the July 2023 OMB delineation.
How many ZIP codes are in Pike County?
16 ZIP Code Tabulation Areas have land in Pike County, and 15 of them have most of their land inside the county. Census ZIP Code Tabulation Areas approximate USPS ZIP Code areas.
How does Pike County compare with U.S. states?
It has less land than every state. Rhode Island, the smallest, has 1.2 times as much land.
How many acres of land are in Pike County?
The land measurement converts to approximately 532,065 acres. Including water, total area is approximately 543,247 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.