Carter County area

Carter County, Oklahoma covers 833.8 square miles: 822.3 square miles of land and 11.5 square miles of water. Its county seat is Ardmore. An estimated 48,910 people lived there in 2025.

Official Census measurements · GEOID 400192026 Gazetteer · retrieved September 27, 2026
Land area822.3 mi²
Water area11.5 mi²
Population (2025)48,910
People per mi²59

County outline

Generalized outline of Carter 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 Carter County is located

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

Area breakdown

Land accounts for 98.6% of Carter County’s measured area and water for 1.4%. Its combined area converts to 2,159.5 square kilometers or approximately 533,620 acres.

Green: land · blue: water

MeasurementSquare milesSquare kilometersAcres
Land822.3012,129.75526,272.6
Water11.4829.7337,347.2
Total833.7812,159.483533,619.8

How Carter County compares

By original Census land area, Carter County ranks #36 of 77 in Oklahoma and #1030 of 3,222 nationally. National rankings include the 50 states, District of Columbia, and Puerto Rico.

Its land area is 1.024 times the Oklahoma county-equivalent median of 802.7 square miles. It accounts for 1.2% of the combined county land area in the state.

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

Population and density of Carter County

The Census Bureau estimates that 48,910 people lived in Carter County on July 1, 2025. That ranks #1,041 of 3,222 county equivalents nationally and #20 of 77 in Oklahoma. Since the April 1, 2020 estimates base of 48,003, the population has grown by 907 (+1.9%), compared with +4.1% for Oklahoma as a whole.

With 822.3 square miles of land, that is 59 people per square mile (23 per km²), placing Carter County #1,393 nationally for density and #19 in Oklahoma. The median county equivalent has 47 people per square mile; the Oklahoma median is 28. Put another way, there are about 11 acres of land per resident.

Estimated population, 2020–2025 · line scaled to this county’s own range
July 1202020212022202320242025
Estimate48,04048,26048,48548,89749,16848,910
Change—+220+225+412+271−258

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 Carter County

9 incorporated places lie at least partly in Carter County. Together they are home to 36,392 people (74.4%); the other 12,518 (25.6%) live outside any incorporated place, in unincorporated communities and rural areas.

The largest is Ardmore city, with 24,956 residents in the county. Among places with at least 1,000 residents in 2020, Lone Grove city grew fastest since then (+5%).

Incorporated placePopulation 2025Since 2020Land mi²
Ardmore cityCounty seat24,956+1.1%49.8
Lone Grove city5,244+5%17.6
Healdton city2,350+0%16.1
Wilson city1,439+2.5%5.644
Dickson town1,363+2.3%14
Springer town701+2.2%14.9
Gene Autry town156+3.3%4.042
Tatums town118+2.6%2.002
Ratliff City town650%1.122

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

Metropolitan area

Carter County is a central county of the Ardmore, OK Micropolitan Statistical Area. Carter County is the area’s only county equivalent, so the micro area has the same 822.3 square miles of land. By combined land it ranks #255 of 542 micropolitan areas, and #234 by population.

ZIP codes

16 ZIP Code Tabulation Areas have land in Carter County; 12 of them have most of their land inside the county, and the others mainly cover neighboring areas.

73401734257343573436734377343873443734447344673453734567345873463734817348773488

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 Carter County

Carter County shares a land border with 7 county equivalents. It has more land than 6 of them. The largest neighbor is Stephens County (870.2 mi²) and the smallest is Marshall County (371.5 mi²). Together with its neighbors, Carter County forms a block of 5,198.4 mi² of land, of which it holds 15.8%.

Map of Carter County and the 7 county equivalents that border it Murray County, Oklahoma: 416.4 mi² landLove County, Oklahoma: 513.9 mi² landStephens County, Oklahoma: 870.2 mi² landJefferson County, Oklahoma: 759 mi² landGarvin County, Oklahoma: 802.1 mi² landJohnston County, Oklahoma: 643.1 mi² landMarshall County, Oklahoma: 371.5 mi² land
Carter 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. CarterCompare
Stephens County870.21.1× largerCompare
Garvin County802.1about the sameCompare
Jefferson County7591.1× smallerCompare
Johnston County643.11.3× smallerCompare
Love County513.91.6× smallerCompare
Murray County416.42× smallerCompare
Marshall County371.52.2× smallerCompare

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

Carter County has less land than any of the 50 states. Rhode Island, the smallest state by land area, has 1,033.9 mi², about 1.3 times as much. Oklahoma’s county land could hold about 83 areas the size of Carter County.

Land area: Carter County and the closest-sized states
Carter County822.3 mi²
Rhode Island1,033.9 mi²

Another way to picture it: the same land area would fill a square about 28.7 miles (46.1 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 Carter County?

Carter County has more land than 2,192 of the other 3,221 county equivalents in the dataset.

Land area compared with the typical county equivalent
Carter County822.3 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 Carter County at #1,112 nationally by total area, 82 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 1.4%, compared with a national county-equivalent median of 1.2% — 0.2 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 Carter County in the national ranking. They can be in different states and are not necessarily geographic neighbors.

Land rankCounty equivalentLand mi²Comparison
#1029Stoddard County, Missouri823.1Compare
#1030Carter County, Oklahoma822.3This county
#1031Solano County, California821.7Compare

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 34.251848, -97.287927. 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: 2,129,750,461 m²; AWATER: 29,733,325 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 Carter County?

Carter County, Oklahoma has 822.3 square miles (2,129.7 km²) of land and 11.5 square miles of water, for a total area of 833.8 square miles. It ranks #1030 of 3,222 U.S. county equivalents by land area.

Is Carter County the largest county in Oklahoma?

No. Carter County ranks #36 of 77 in Oklahoma by land area. The largest is Osage County, with 2,246.7 square miles of land.

What counties border Carter County?

Carter County shares a land border with Murray County, Love County, Stephens County, Jefferson County, Garvin County, Johnston County, and Marshall County.

What is the population of Carter County?

The Census Bureau estimates Carter County had 48,910 residents on July 1, 2025, ranking #1,041 of 3,222 county equivalents. That is 59 people per square mile of land.

What is the county seat of Carter County?

The county seat of Carter County is Ardmore.

What cities and towns are in Carter County?

Carter County has 9 incorporated places. The most populous five are Ardmore city, Lone Grove city, Healdton city, Wilson city, and Dickson town; 12,518 residents live outside any incorporated place.

Is Carter County part of a metropolitan area?

Yes. It is a central county of the Ardmore, OK Micropolitan Statistical Area.

How many ZIP codes are in Carter County?

16 ZIP Code Tabulation Areas have land in Carter County, and 12 of them have most of their land inside the county. Census ZIP Code Tabulation Areas approximate USPS ZIP Code areas.

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

It has less land than every state. Rhode Island, the smallest, has 1.3 times as much land.

How many acres of land are in Carter County?

The land measurement converts to approximately 526,273 acres. Including water, total area is approximately 533,620 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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