County Maps US

Ottawa County, Ohio

A county in Ohio, ranked 62 of 88 by population.

CountyFIPS 39123

Within Ohio
Ottawa County, highlighted, with the areas around it. Boundaries generalised from the 2025 Census cartographic boundary file; neighbour fills carry no data. The dot marks Port Clinton, the county seat, located via the 2025 Census Gazetteer.

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Population
39,481
-822 (-2.0%) since 2020
Land area
254.7
square miles. A further 56.5% of the total area is water
Population density
155
people per square mile, computed rather than published
County seat
Port Clinton
Seat of county government.
Established
1840
185 years ago
Largest city
Port Clinton city
Population 5,875.

Sources: US Census Bureau, Population Estimates Program, Vintage 2025 Population Estimates, released 26 March 2026; US Census Bureau, Gazetteer Files, 2025 Gazetteer Files, released 10 September 2025; Wikidata (CC0), Wikidata. Retrieved 30 August 2026.

Satellite view

Aerial imagery of Ottawa County with its boundary drawn on top. A map shows you the shape; this shows you what is inside it, and which side of the line a place falls on.

Aerial view of Ottawa County, Ohio from the USGS National Map, with its boundary outlined
Imagery: USGS National Map, USGS Imagery Only, public domain, requested from USGS by your browser when you reach this point on the page, at 800 by 448 pixels. The boundary is the 2025 Census cartographic boundary file, reprojected to Web Mercator to match the imagery. You can also open the USGS National Map viewer.

Where Ottawa County ranks

Position among the 88 counties of Ohio, and among all 3,144 US counties and county-equivalents. Computed from the figures on this page.

MeasureValueIn OhioNationally
Population39,48162nd of 881,201st of 3,144
Land area254.7 sq mi86th of 882,897th of 3,144
Population density155 per sq mi34th of 88682nd of 3,144
Median household income$76,10119th of 88775th of 3,143

Full data for Ottawa County

Every figure below is attributed to the Census Bureau product it came from, with the vintage of that product.
MeasureValueSource and vintage
Population39,481Vintage 2025 Population Estimates
Population in 202040,303Vintage 2025 Population Estimates
2020 estimates base?40,367Vintage 2025 Population Estimates
Land area254.7 sq mi2025 Gazetteer Files
Water area330.4 sq mi2025 Gazetteer Files
Total area585.1 sq mi2025 Gazetteer Files
Population density?155 per sq miComputed: Vintage 2025 estimates divided by 2025 Gazetteer land area
Median household income$76,101American Community Survey 2020-2024 5-Year Estimates
Median home value$219,900American Community Survey 2020-2024 5-Year Estimates
Median age50.6American Community Survey 2020-2024 5-Year Estimates
Households18,504American Community Survey 2020-2024 5-Year Estimates
Housing units28,911American Community Survey 2020-2024 5-Year Estimates

Sources: US Census Bureau, Population Estimates Program, Vintage 2025 Population Estimates, released 26 March 2026; US Census Bureau, Gazetteer Files, 2025 Gazetteer Files, released 10 September 2025; US Census Bureau, American Community Survey, American Community Survey 2020-2024 5-Year Estimates, released 29 January 2026. Population density is computed here, not published: it divides the Vintage 2025 population estimate by the 2025 Gazetteer land area, which are two different Census products. Retrieved 30 August 2026.

How the population changed

The Census Bureau publishes the components behind an estimate, not just the total. For the year to July 2025:

Births minus deaths
-251
289 births, 540 deaths
Net migration
+2
More people moved in than moved out.

Source: US Census Bureau, Population Estimates Program, Vintage 2025 Population Estimates, released 26 March 2026. Retrieved 30 August 2026.

The 4 areas bordering Ottawa County

Ordered by the length of the border actually shared, which the Census Bureau publishes in its county adjacency file and which no other county reference presents.

Bordering areaStateShared borderPopulation
Erie CountyOhio37 mi73,296
Lucas CountyOhio30 mi423,347
Sandusky CountyOhio27 mi58,655
Wood CountyOhio8.2 mi134,176

Source: US Census Bureau, County Adjacency File, 2025 County Adjacency File, released 15 September 2025. Retrieved 30 August 2026.

All 88 counties of Ohio

Open the interactive Ohio county map, or jump straight to any of them.

Data on this page last rebuilt 30 August 2026. How these figures are produced.