Tillman County area

Tillman County, Oklahoma covers 879.2 square miles: 871.1 square miles of land and 8.068 square miles of water. Its county seat is Frederick. An estimated 6,780 people lived there in 2025.

Official Census measurements · GEOID 401412026 Gazetteer · retrieved September 27, 2026
Land area871.1 mi²
Water area8.068 mi²
Population (2025)6,780
People per mi²7.8

County outline

Generalized outline of Tillman County, Oklahoma
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 Tillman County is located

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

Area breakdown

Land accounts for 99.1% of Tillman County’s measured area and water for 0.9%. Its combined area converts to 2,277.1 square kilometers or approximately 562,689 acres.

Green: land · blue: water

MeasurementSquare milesSquare kilometersAcres
Land871.1342,256.227557,525.8
Water8.06820.8965,163.5
Total879.2022,277.123562,689.3

How Tillman County compares

By original Census land area, Tillman County ranks #33 of 77 in Oklahoma and #936 of 3,222 nationally. National rankings include the 50 states, District of Columbia, and Puerto Rico.

Its land area is 1.085 times the Oklahoma county-equivalent median of 802.7 square miles. It accounts for 1.3% of the combined county land area in the state.

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

Population and density of Tillman County

The Census Bureau estimates that 6,780 people lived in Tillman County on July 1, 2025. That ranks #2,748 of 3,222 county equivalents nationally and #64 of 77 in Oklahoma. Since the April 1, 2020 estimates base of 6,967, the population has declined by 187 (−2.7%), compared with +4.1% for Oklahoma as a whole.

With 871.1 square miles of land, that is 7.8 people per square mile (3 per km²), placing Tillman County #2,728 nationally for density and #65 in Oklahoma. The median county equivalent has 47 people per square mile; the Oklahoma median is 28. Put another way, there are about 82 acres of land per resident.

Estimated population, 2020–2025 · line scaled to this county’s own range
July 1202020212022202320242025
Estimate6,9507,0446,9756,8836,7986,780
Change—+94−69−92−85−18

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 Tillman County

8 incorporated places lie at least partly in Tillman County. Together they are home to 5,562 people (82%); the other 1,218 (18%) live outside any incorporated place, in unincorporated communities and rural areas.

The largest is Frederick city, with 3,371 residents in the county.

Incorporated placePopulation 2025Since 2020Land mi²
Frederick cityCounty seat3,371−3.2%4.947
Grandfield city889−2.7%0.835
Tipton town840−2.7%1.171
Davidson town238−2.1%0.481
Manitou town171−0.6%0.314
Hollister town38−2.6%0.268
Loveland town150%0.226
Chattanooga townAlso in 1 other county0—0.524

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

Metropolitan area

Tillman 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

9 ZIP Code Tabulation Areas have land in Tillman County; 7 of them have most of their land inside the county, and the others mainly cover neighboring areas.

735287353073542735467355173553735557356673570

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 Tillman County

Tillman County shares a land border with 6 county equivalents, including 2 in Texas. It has more land than 3 of them. The largest neighbor is Comanche County (1,069.3 mi²) and the smallest is Wichita County (627.6 mi²). Together with its neighbors, Tillman County forms a block of 5,989.4 mi² of land, of which it holds 14.5%.

Map of Tillman County and the 6 county equivalents that border it Jackson County, Oklahoma: 802.7 mi² landWilbarger County, Texas: 970.9 mi² landComanche County, Oklahoma: 1,069.3 mi² landWichita County, Texas: 627.6 mi² landCotton County, Oklahoma: 632.6 mi² landKiowa County, Oklahoma: 1,015.1 mi² land
Tillman 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. TillmanCompare
Comanche County1,069.31.2× largerCompare
Kiowa County1,015.11.2× largerCompare
Wilbarger CountyTexas970.91.1× largerCompare
Jackson County802.71.1× smallerCompare
Cotton County632.61.4× smallerCompare
Wichita CountyTexas627.61.4× smallerCompare

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

Tillman 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. Oklahoma’s county land could hold about 79 areas the size of Tillman County.

Land area: Tillman County and the closest-sized states
Tillman County871.1 mi²
Rhode Island1,033.9 mi²

Another way to picture it: the same land area would fill a square about 29.5 miles (47.5 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 Tillman County?

Tillman County has more land than 2,286 of the other 3,221 county equivalents in the dataset.

Land area compared with the typical county equivalent
Tillman County871.1 mi²
Oklahoma median802.7 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 Tillman County at #1,030 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 Tillman County in the national ranking. They can be in different states and are not necessarily geographic neighbors.

Land rankCounty equivalentLand mi²Comparison
#935Pender County, North Carolina871.3Compare
#936Tillman County, Oklahoma871.1This county
#937Langlade County, Wisconsin870.7Compare

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 34.371085, -98.931701. 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: 2,256,226,925 m²; AWATER: 20,895,052 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 Tillman County?

Tillman County, Oklahoma has 871.1 square miles (2,256.2 km²) of land and 8.068 square miles of water, for a total area of 879.2 square miles. It ranks #936 of 3,222 U.S. county equivalents by land area.

Is Tillman County the largest county in Oklahoma?

No. Tillman County ranks #33 of 77 in Oklahoma by land area. The largest is Osage County, with 2,246.7 square miles of land.

What counties border Tillman County?

Tillman County shares a land border with Jackson County, Wilbarger County, Texas, Comanche County, Wichita County, Texas, Cotton County, and Kiowa County.

What is the population of Tillman County?

The Census Bureau estimates Tillman County had 6,780 residents on July 1, 2025, ranking #2,748 of 3,222 county equivalents. That is 7.8 people per square mile of land.

What is the county seat of Tillman County?

The county seat of Tillman County is Frederick.

What cities and towns are in Tillman County?

Tillman County has 8 incorporated places. The most populous five are Frederick city, Grandfield city, Tipton town, Davidson town, and Manitou town; 1,218 residents live outside any incorporated place.

Is Tillman County part of a metropolitan area?

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

How many ZIP codes are in Tillman County?

9 ZIP Code Tabulation Areas have land in Tillman County, and 7 of them have most of their land inside the county. Census ZIP Code Tabulation Areas approximate USPS ZIP Code areas.

How does Tillman 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 Tillman County?

The land measurement converts to approximately 557,526 acres. Including water, total area is approximately 562,689 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

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