Seneca County, Ohio Population 2026
Updated April 2026 · US Census ACS 2023 5-Year Estimates · 47th-largest in Ohio
The population of Seneca County, Ohio is 54,861 as of the 2023 American Community Survey, making it the 47th-largest county in Ohio. The median household income is $65,020, the median home value is $136,200, and the median age is 40.5.
The population of Seneca County has declined 3.3% since 2010 (56,619 → 54,730), a -0.24% annualized rate.
54,861
Population
-0.24%
Annual growth
100
People / sq mi
$65,020
Median Income
$136,200
Median Home Value
Seneca County covers 551 sq mi of land at 99.6 people per square mile.
About Seneca County, OH
Seneca County is distinguished by its share of foreign-born residents, 10.4% of the population. Seneca County is a county in Ohio with a population of 54,861. It ranks #47 among counties in Ohio by population.
The typical household here earns about $65,020, below the US median of $78,538. Poverty runs at 8.3%, below the national 12.4%. The typical home is valued at $136,200, with typical rent around $814.
Degree attainment is mid-range for US counties: 20.7% of adults hold a four-year degree, below the national 35.0%. Remote work is on the lower side here, at 5.0%, below the national 14.0%, and the average commute runs about 21 minutes each way.
Seneca County Population History (2010-2024)
The county of Seneca County had a population of 56,619 in 2010 and 54,730 in 2024, a -3.3% growth over 14 years. The peak was 56,619 in 2010. Average annual growth rate: -0.24%.
54,730
Population (2024)
56,619
Population (2010)
56,619
Peak (2010)
-0.24%
Avg Annual Growth
| Year | Population |
|---|---|
| 2010 | 56,619 |
| 2011 | 56,526 |
| 2012 | 56,117 |
| 2013 | 55,860 |
| 2014 | 55,819 |
| 2015 | 55,672 |
| 2016 | 55,517 |
| 2017 | 55,322 |
| 2018 | 55,256 |
| 2019 | 55,220 |
| 2020 | 55,055 |
| 2021 | 54,876 |
| 2022 | 54,563 |
| 2023 | 54,628 |
| 2024 | 54,730 |
Race & Ethnicity
| White | 90.5% |
| Black or African American | 2.7% |
| Asian | 0.0% |
| Hispanic or Latino (any race) | 1.1% |
| Two or More Races | 0.0% |
Age & Sex
40.5
Median Age
49.6%
Female
50.4%
Male
18.7%
Age 65+
Age Distribution
Children (under 15): 17.5% · Seniors (65+): 18.7%
Income & Poverty
| Median household income | $65,020$-4,660 vs state |
| Mean household income | $79,613 |
| Per-capita income | $32,716 |
| Poverty rate | 8.3%-0.9% vs state |
| Unemployment rate | 2.5% |
| Employment-to-population | 59.9% |
Top Industries by Employment
The largest employment sector in Seneca County is manufacturing, accounting for 28.4% of workers.
How residents commute
0.2%
Drive alone
4.2%
Carpool
81.3%
Public transit
5.0%
Work from home
20.5 min
Avg commute
Housing
$136,200$-63,000 vs state
Median home value
$814
Median rent
73.4%
Homeownership rate
23,968
Total housing units
92.2%
Occupied
7.8%
Vacant
26.6%
Renter-occupied
Social & access
94.7%
With health insurance
92.0%
With broadband internet
10.4%
Foreign-born
6.9%
Veterans (18+)
14.9%
With a disability
96.9%
Speak language other than English at home
Education
93.2%
High School+
20.7%
Bachelor's+
Largest cities in Ohio
Other counties in Ohio
Part of Ohio
Metro areas in Ohio
County rankings
Frequently Asked Questions
Seneca County, Ohio has a population of 54,861 according to the US Census Bureau's 2023 American Community Survey 5-year estimates, making it the 47th-largest county in Ohio. Population density is 100 people per square mile.
The population of Seneca County has declined 3.3% since 2010 (56,619 → 54,730), a -0.24% annualized rate.
The median household income in Seneca County, Ohio is $65,020, with mean (average) household income of $79,613 and per-capita income of $32,716. 8.3% of residents live below the federal poverty level.
In Seneca County, the largest racial and ethnic groups are White (90.5%), Black or African American (2.7%), Hispanic or Latino (1.1%). Figures are from the US Census Bureau's 2023 ACS 5-year estimates and reflect self-reported responses.
The median age in Seneca County, Ohio is 40.5 years. Residents are 49.6% female and 50.4% male.
The median home value in Seneca County is $136,200 and median monthly rent is $814. 73.4% of occupied housing units are owner-occupied. The county has 23,968 total housing units, 7.8% of which are vacant.
The largest employment sector in Seneca County, Ohio is manufacturing, employing 28.4% of workers. The unemployment rate is 2.5%.
Columbus is among the largest cities associated with Seneca County, Ohio, with a population of 906,480.
Seneca County, OH Climate
Seneca County, OH has an average annual temperature of 9.8°C (50°F) and receives about 920 mm of precipitation per year. The warmest month is July and the coldest is January. Figures are 1970–2000 climate normals.
9.8°C
Avg Temp
920
Precip (mm/yr)
Jul
Hottest Month
Jan
Coldest Month
| Month | Avg (°C/°F) | Precip |
|---|---|---|
| January | -4° / 24° | 53 mm |
| February | -3° / 27° | 48 mm |
| March | 3° / 37° | 67 mm |
| April | 9° / 48° | 85 mm |
| May | 15° / 59° | 94 mm |
| June | 20° / 69° | 104 mm |
| July | 23° / 73° | 91 mm |
| August | 22° / 71° | 93 mm |
| September | 18° / 64° | 80 mm |
| October | 11° / 52° | 59 mm |
| November | 5° / 41° | 75 mm |
| December | -1° / 30° | 71 mm |
1970–2000 normals from WorldClim 2.1 (~9 km grid). Precipitation can be less precise near mountains or coastlines, where rainfall varies sharply over short distances.
Best time to visit Seneca County, OH
The most comfortable months to visit Seneca County, OH are typically August, June and July, when temperatures are mildest and rainfall is relatively low. The hottest month is July (around 29°C high). The coldest is January (near -9°C low). June is usually the wettest month.
Where to stay near Seneca County
Visiting or relocating to Seneca County, OH? Compare hotels and short-term rentals across the county — live availability and prices.
Top-rated places to stay near Seneca County
Availability and prices from Stay22 partners (Booking.com, Vrbo, Expedia). We may earn a commission from bookings, at no extra cost to you.
Planning a move to Seneca County?
Get relocation and cost-of-living insights for Seneca County, OH by email. No spam, unsubscribe anytime.
More from Ohio
Population 1,321,635
Population 1,249,418
Population 827,878
Population 538,087
Full rankings of Ohio counties
Statewide data for Ohio
Population, race, income, age, and trends across Ohio
Data from the American Community Survey (ACS) 5-Year estimates.
Source: U.S. Census Bureau ACS, 2026.