County outline
Where Ottawa County is located
Area breakdown
Land accounts for 97.2% of Ottawa County’s measured area and water for 2.8%. Its combined area converts to 1,255.1 square kilometers or approximately 310,148 acres.
Green: land · blue: water
| Measurement | Square miles | Square kilometers | Acres |
|---|---|---|---|
| Land | 470.817 | 1,219.41 | 301,322.9 |
| Water | 13.789 | 35.713 | 8,825 |
| Total | 484.606 | 1,255.124 | 310,147.8 |
How Ottawa County compares
By original Census land area, Ottawa County ranks #74 of 77 in Oklahoma and #2189 of 3,222 nationally. National rankings include the 50 states, District of Columbia, and Puerto Rico.
Its land area is 0.587 times the Oklahoma county-equivalent median of 802.7 square miles. It accounts for 0.7% of the combined county land area in the state.
See the complete Oklahoma ranking · What counts as a county equivalent?
Population and density of Ottawa County
The Census Bureau estimates that 30,438 people lived in Ottawa County on July 1, 2025. That ranks #1,473 of 3,222 county equivalents nationally and #32 of 77 in Oklahoma. Since the April 1, 2020 estimates base of 30,289, the population has grown by 149 (+0.5%), compared with +4.1% for Oklahoma as a whole.
With 470.8 square miles of land, that is 65 people per square mile (25 per km²), placing Ottawa County #1,326 nationally for density and #16 in Oklahoma. The median county equivalent has 47 people per square mile; the Oklahoma median is 28. Put another way, there are about 9.9 acres of land per resident.
| July 1 | 2020 | 2021 | 2022 | 2023 | 2024 | 2025 |
|---|---|---|---|---|---|---|
| Estimate | 30,240 | 30,387 | 30,369 | 30,291 | 30,429 | 30,438 |
| Change | — | +147 | −18 | −78 | +138 | +9 |
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 Ottawa County
8 incorporated places lie at least partly in Ottawa County. Together they are home to 18,757 people (61.6%); the other 11,681 (38.4%) live outside any incorporated place, in unincorporated communities and rural areas.
The largest is Miami city, with 12,893 residents in the county. Among places with at least 1,000 residents in 2020, Fairland town grew fastest since then (+0.2%).
| Incorporated place | Population 2025 | Since 2020 | Land mi² |
|---|---|---|---|
| Miami cityCounty seat | 12,893 | −0.8% | 11.1 |
| Commerce city | 2,260 | −0.1% | 2.312 |
| Fairland town | 1,100 | +0.2% | 1.12 |
| Quapaw town | 838 | +2.6% | 0.826 |
| Afton town | 753 | +1.2% | 2.081 |
| Wyandotte town | 488 | +1.5% | 1.36 |
| North Miami town | 294 | +1.7% | 0.189 |
| Peoria town | 131 | +4% | 0.243 |
Population: U.S. Census Bureau Vintage 2025 subcounty estimates, counting only the part of each place inside Ottawa County. Land: 2026 Census Gazetteer, for the whole place even where it extends into other counties. How communities are listed.
Metropolitan area
Ottawa County is a central county of the Miami, OK Micropolitan Statistical Area. Ottawa County is the area’s only county equivalent, so the micro area has the same 470.8 square miles of land. By combined land it ranks #448 of 542 micropolitan areas, and #433 by population. It belongs to the Joplin-Miami, MO-OK-KS Combined Statistical Area.
ZIP codes
10 ZIP Code Tabulation Areas have land in Ottawa County; 7 of them have most of their land inside the county, and the others mainly cover neighboring areas.
74331743337433974343743447435474358743607436374370
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 Ottawa County
Ottawa County shares a land border with 5 county equivalents, including 3 in Kansas and Missouri. Each of them has more land than Ottawa County. The largest neighbor is Craig County (761.3 mi²) and the smallest is McDonald County (539.4 mi²). Together with its neighbors, Ottawa County forms a block of 3,721.5 mi² of land, of which it holds 12.7%.
| Bordering county equivalent | Land mi² | Size vs. Ottawa | Compare |
|---|---|---|---|
| Craig County | 761.3 | 1.6× larger | Compare |
| Delaware County | 737.7 | 1.6× larger | Compare |
| Newton CountyMissouri | 624.8 | 1.3× larger | Compare |
| Cherokee CountyKansas | 587.6 | 1.2× larger | Compare |
| McDonald CountyMissouri | 539.4 | 1.1× larger | Compare |
How big is Ottawa County compared with U.S. states?
Ottawa County has less land than any of the 50 states. Rhode Island, the smallest state by land area, has 1,033.9 mi², about 2.2 times as much. Oklahoma’s county land could hold about 146 areas the size of Ottawa County.
Another way to picture it: the same land area would fill a square about 21.7 miles (34.9 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 Ottawa County?
Ottawa County has more land than 1,033 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 Ottawa County at #2,229 nationally by total area, 40 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 2.8%, compared with a national county-equivalent median of 1.2% — 1.7 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 Ottawa County in the national ranking. They can be in different states and are not necessarily geographic neighbors.
| Land rank | County equivalent | Land mi² | Comparison |
|---|---|---|---|
| #2188 | Hancock County, Georgia | 471.1 | Compare |
| #2189 | Ottawa County, Oklahoma | 470.8 | This county |
| #2190 | Nelson County, Virginia | 470.7 | 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 36.835764, -94.802681. 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: 1,219,410,539 m²; AWATER: 35,714,098 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 Ottawa County?
Ottawa County, Oklahoma has 470.8 square miles (1,219.4 km²) of land and 13.8 square miles of water, for a total area of 484.6 square miles. It ranks #2189 of 3,222 U.S. county equivalents by land area.
Is Ottawa County the largest county in Oklahoma?
No. Ottawa County ranks #74 of 77 in Oklahoma by land area. The largest is Osage County, with 2,246.7 square miles of land.
What counties border Ottawa County?
Ottawa County shares a land border with Craig County, Cherokee County, Kansas, Delaware County, Newton County, Missouri, and McDonald County, Missouri.
What is the population of Ottawa County?
The Census Bureau estimates Ottawa County had 30,438 residents on July 1, 2025, ranking #1,473 of 3,222 county equivalents. That is 65 people per square mile of land.
What is the county seat of Ottawa County?
The county seat of Ottawa County is Miami.
What cities and towns are in Ottawa County?
Ottawa County has 8 incorporated places. The most populous five are Miami city, Commerce city, Fairland town, Quapaw town, and Afton town; 11,681 residents live outside any incorporated place.
Is Ottawa County part of a metropolitan area?
Yes. It is a central county of the Miami, OK Micropolitan Statistical Area.
How many ZIP codes are in Ottawa County?
10 ZIP Code Tabulation Areas have land in Ottawa 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 Ottawa County compare with U.S. states?
It has less land than every state. Rhode Island, the smallest, has 2.2 times as much land.
How many acres of land are in Ottawa County?
The land measurement converts to approximately 301,323 acres. Including water, total area is approximately 310,148 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.