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 a county in Ohio with a population of 54,861. It ranks #47 among counties in Ohio by population. The median age is 40.5, older than the national median. The population is 50.4% male and 49.6% female.
The median household income in Seneca County is $65,020, below the US median of $74,580. 8.3% of residents live below the federal poverty level. Home values sit at a median of $136,200, with monthly rent averaging $814. The homeownership rate of 73.4% is higher than the national rate of 64.8%.
Educational attainment in Seneca County reflects 20.7% of adults 25 and older holding a bachelor's degree or higher, below the national average of 34.3%. Roughly 5.0% of workers primarily work from home, below the national work-from-home rate of 14.2%. The average commute is 20.5 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+
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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.
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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.