Phillips County area

Phillips County, Colorado covers 688 square miles: 687.9 square miles of land and 0.117 square miles of water. Its county seat is Holyoke. An estimated 4,420 people lived there in 2025.

Official Census measurements · GEOID 080952026 Gazetteer · retrieved September 27, 2026
Land area687.9 mi²
Water area0.117 mi²
Population (2025)4,420
People per mi²6.4

County outline

Generalized outline of Phillips County, Colorado
2025 Census cartographic boundary, fitted to this frame. County maps are not at a common scale. The 2026 area measurements below come from the separate Gazetteer release. Map source and limitations.

Where Phillips County is located

Phillips County highlighted on a map of all U.S. county equivalents. About the maps

Area breakdown

Land accounts for 100% of Phillips County’s measured area and water for 0%. Its combined area converts to 1,782 square kilometers or approximately 440,349 acres.

Green: land · blue: water

MeasurementSquare milesSquare kilometersAcres
Land687.9281,781.725440,273.9
Water0.1170.30374.9
Total688.0451,782.028440,348.8

How Phillips County compares

By original Census land area, Phillips County ranks #54 of 64 in Colorado and #1362 of 3,222 nationally. National rankings include the 50 states, District of Columbia, and Puerto Rico.

Its land area is 0.481 times the Colorado county-equivalent median of 1,431.5 square miles. It accounts for 0.7% of the combined county land area in the state.

See the complete Colorado ranking · What counts as a county equivalent?

Population and density of Phillips County

The Census Bureau estimates that 4,420 people lived in Phillips County on July 1, 2025. That ranks #2,935 of 3,222 county equivalents nationally and #54 of 64 in Colorado. Since the April 1, 2020 estimates base of 4,534, the population has declined by 114 (−2.5%), compared with +4.1% for Colorado as a whole.

With 687.9 square miles of land, that is 6.4 people per square mile (2.5 per km²), placing Phillips County #2,787 nationally for density and #41 in Colorado. The median county equivalent has 47 people per square mile; the Colorado median is 11. Put another way, there are about 100 acres of land per resident.

Estimated population, 2020–2025 · line scaled to this county’s own range
July 1202020212022202320242025
Estimate4,5284,5044,4444,4604,4544,420
Change—−24−60+16−6−34

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 Phillips County

3 incorporated places lie at least partly in Phillips County. Together they are home to 3,263 people (73.8%); the other 1,157 (26.2%) live outside any incorporated place, in unincorporated communities and rural areas.

The largest is Holyoke city, with 2,264 residents in the county.

Incorporated placePopulation 2025Since 2020Land mi²
Holyoke cityCounty seat2,264−3.5%2.473
Haxtun town951−3.3%0.614
Paoli town48−4%0.296

Population: U.S. Census Bureau Vintage 2025 subcounty estimates, counting only the part of each place inside Phillips County. Land: 2026 Census Gazetteer, for the whole place even where it extends into other counties. How communities are listed.

Metropolitan area

Phillips 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

4 ZIP Code Tabulation Areas have land in Phillips County, and each lies mostly inside the county.

80721807318073480746

ZIP Code Tabulation Areas are the Census Bureau’s approximations of USPS ZIP Code service areas, from the 2020 Census relationship files. Post-office-box and single-address ZIP Codes have no tabulation area.

Counties bordering Phillips County

Phillips County shares a land border with 5 county equivalents, including 2 in Nebraska. It has more land than 1 of them. The largest neighbor is Yuma County (2,364.4 mi²) and the smallest is Sedgwick County (548 mi²). Together with its neighbors, Phillips County forms a block of 7,216.7 mi² of land, of which it holds 9.5%.

Map of Phillips County and the 5 county equivalents that border it Yuma County, Colorado: 2,364.4 mi² landSedgwick County, Colorado: 548 mi² landLogan County, Colorado: 1,838.6 mi² landChase County, Nebraska: 894.4 mi² landPerkins County, Nebraska: 883.3 mi² land
Phillips County (dark) and its bordering county equivalents. Select a neighbor to open its profile. Drawn from the 2025 Census cartographic boundaries in an equal-area projection. How borders are determined.
Bordering county equivalentLand mi²Size vs. PhillipsCompare
Yuma County2,364.43.4× largerCompare
Logan County1,838.62.7× largerCompare
Chase CountyNebraska894.41.3× largerCompare
Perkins CountyNebraska883.31.3× largerCompare
Sedgwick County5481.3× smallerCompare

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

Phillips County has less land than any of the 50 states. Rhode Island, the smallest state by land area, has 1,033.9 mi², about 1.5 times as much. Colorado’s county land could hold about 151 areas the size of Phillips County.

Land area: Phillips County and the closest-sized states
Phillips County687.9 mi²
Rhode Island1,033.9 mi²

Another way to picture it: the same land area would fill a square about 26.2 miles (42.2 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 Phillips County?

Phillips County has more land than 1,860 of the other 3,221 county equivalents in the dataset.

Land area compared with the typical county equivalent
Phillips County687.9 mi²
Colorado median1,431.5 mi²
National median604.5 mi²

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 Phillips County at #1,469 nationally by total area, 107 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%, compared with a national county-equivalent median of 1.2% — 1.2 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 Phillips County in the national ranking. They can be in different states and are not necessarily geographic neighbors.

Land rankCounty equivalentLand mi²Comparison
#1361Cambria County, Pennsylvania688Compare
#1362Phillips County, Colorado687.9This county
#1363Codington County, South Dakota687.6Compare

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 40.594712, -102.345105. 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: 1,781,724,974 m²; AWATER: 301,808 m². Rankings use ALAND; exact ties use ascending GEOID. Tables preserve Census-published square miles to three decimals, with conversions based on those values.

Download the official county source ZIP ↗ · Methodology

Common questions

How big is Phillips County?

Phillips County, Colorado has 687.9 square miles (1,781.7 km²) of land and 0.117 square miles of water, for a total area of 688 square miles. It ranks #1362 of 3,222 U.S. county equivalents by land area.

Is Phillips County the largest county in Colorado?

No. Phillips County ranks #54 of 64 in Colorado by land area. The largest is Las Animas County, with 4,772.9 square miles of land.

What counties border Phillips County?

Phillips County shares a land border with Yuma County, Sedgwick County, Logan County, Chase County, Nebraska, and Perkins County, Nebraska.

What is the population of Phillips County?

The Census Bureau estimates Phillips County had 4,420 residents on July 1, 2025, ranking #2,935 of 3,222 county equivalents. That is 6.4 people per square mile of land.

What is the county seat of Phillips County?

The county seat of Phillips County is Holyoke.

What cities and towns are in Phillips County?

Phillips County has 3 incorporated places. The most populous are Holyoke city, Haxtun town, and Paoli town; 1,157 residents live outside any incorporated place.

Is Phillips County part of a metropolitan area?

No. Phillips County is outside every metropolitan and micropolitan statistical area in the July 2023 OMB delineation.

How many ZIP codes are in Phillips County?

4 ZIP Code Tabulation Areas have land in Phillips County, and 4 of them have most of their land inside the county. Census ZIP Code Tabulation Areas approximate USPS ZIP Code areas.

How does Phillips County compare with U.S. states?

It has less land than every state. Rhode Island, the smallest, has 1.5 times as much land.

How many acres of land are in Phillips County?

The land measurement converts to approximately 440,274 acres. Including water, total area is approximately 440,349 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.

Cite this county

Download the complete CSV or JSON dataset