Seneca, IL
Population 2,525 · Illinois
About Seneca, IL
Seneca is a small community in Illinois with a population of 2,525 residents. The median household income is $91,065 per year, which is above the national average. The median age in Seneca is 35.2 years.
Housing in Seneca has a median home value of $206,400 and median monthly rent of $988. Of the 971 total housing units, the majority are owner-occupied, with 710 owner-occupied and 217 renter-occupied units.
The unemployment rate in Seneca is 4.2% and the poverty rate is 19.4%. 12.9% of residents hold a bachelor's degree or higher. The average commute time is 29.9 minutes.
Cost of Living in Seneca, IL
Compared to national averages, Seneca has a median household income of $91,065 (21% above the national median of $75,149). Home values average $206,400, which is 16% below the national median. Monthly rent at $988 is 15% below the US average of $1,163. Within Illinois, Seneca's income is 21% above the state average of $75,072, and home values are 25% above the state median of $165,779.
Why Live in Seneca, IL?
Seneca offers a strong local economy with a median household income of $91,065, well above the national average, and affordable housing with a median home value of $206,400, below the US average of $244,900, and rent that’s lower than the national average at $988/month.
Seneca has a population of 2,525 with a median age of 35.2 years. Compare Seneca with other cities to see how it stacks up, or explore all cities in Illinois.
Similar Cities Near Seneca
Cities in Illinois with a similar population size.
| City | Population | Median Income | Home Value | |
|---|---|---|---|---|
| Carrollton | 2,528 | $64,464 | $114,100 | Compare |
| Richmond | 2,530 | $70,379 | $225,800 | Compare |
| Brighton | 2,536 | $74,327 | $123,000 | Compare |
| Tilton | 2,537 | $53,246 | $71,700 | Compare |
| Carthage | 2,508 | $75,179 | $115,600 | Compare |
| Galva | 2,543 | $55,446 | $77,800 | Compare |
| Kenilworth | 2,543 | $250,001 | $1,409,800 | Compare |
| Altamont | 2,500 | $76,198 | $132,200 | Compare |
Demographics
Racial & Ethnic Composition
Economy & Education
Housing
Other Cities in Illinois
Data source: US Census Bureau ACS 5-Year Estimates. Last updated: 2026-04-05.
Compare Seneca With Other Cities
Frequently Asked Questions about Seneca
What is the population of Seneca, IL?
The population of Seneca, IL is 2,525 according to the latest Census data.
What is the median household income in Seneca?
The median household income in Seneca, IL is $91,065 per year.
What is the median home value in Seneca?
The median home value in Seneca, IL is $206,400.
What is the average rent in Seneca?
The median monthly rent in Seneca, IL is $988.
What is the unemployment rate in Seneca?
The unemployment rate in Seneca, IL is 4.2%.