SenecaIL

A town of 2,450, settled in 1854. Healthier than 51% of U.S. towns.

2 bordering townsMap →

Photo: IvoShandor · CC BY-SA 3.0

Population

2,450

−0.8% since 2010

Typical home

$258K

+5.2% in a year

Household income

$87K

median

Median age

35.5

years

Jobs based here

569

A commuter town

What makes Seneca stand out

The thing Seneca does most differently from other towns.

Picked automatically from the data

100 U.S. towns● Seneca

Health

Healthier than 51%

of U.S. towns on CDC estimates

Better than IL on 1 measures, worse on 5.

A commuter town

95% of working residents leave Seneca for work

Where Seneca’s working residents go each day. Line width shows the share.

569jobs based in Seneca

5%of working residents work in town

25 mimedian commute distance

Census LEHD 2023

Seneca’s report card

See the data ↓

Commute25 miHalf of commuters travel less HealthB−Healthier than 51% of U.S. towns Hazards73/100High risk of storm & flood damage Climate85°/16°Summer high · winter low · 25″ snow Housing$258K13% below the IL typical home

Now in Seneca

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Residents weigh in

Seneca is #814 of 820 in IL for “Most walkable”. Fair?

Your answer becomes a post in Seneca’s Town Square.

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Weather

Forecast →

57°

Clear

Tonight L 48°

Upcoming events

Nothing on the calendar.

The data

Ordered by what stands out in Seneca. Another town gets a different order.

Work & commute

Most working residents commute out of Seneca

Most working residents leave Seneca for work: only 5% work in town. The top destinations are Ottawa (11%), Morris (6%) and Marseilles (5%). Half commute less than 25 miles.

5%work in town

Where working residents work

In Seneca5%

Ottawa11%

Morris6%

Marseilles5%

Chicago4%

25 mi

median commute distance

569

jobs based in Seneca

A commuter town

jobs vs. working residents

Census LEHD 2023 · ACSCommute map →

Health

Healthier than 51% of U.S. towns

Seneca beats the Illinois average on 1 of 32 CDC measures and trails it on 5.

B−Health Grade

32 measures vs. Illinois

1 better26 too close to call5 worse

What stands out	Seneca	IL
Fewer uninsured adults	7.7%	9.9%
More smokers	15.8%	12.1%

Morris Hospital & Healthcare Centers

10.7 mi away · emergency room

3 of 3

care shortages: primary care, dental, mental health

43rd

percentile among IL towns

CDC PLACES 2025 · modeled estimates for adults · CMS · HRSAFull health report →

Natural hazards

High risk, with inland flooding at the top

Expected storm and flood damage is higher than in 73% of U.S. communities.

73risk score of 100

FEMA risk score

Inland floodingCold wavesTornadoes

paid flood claims since 1979

federal disasters paid out here

FEMA National Risk Index · OpenFEMANatural hazards →

Climate

Four seasons, pleasant summers

Seneca has chilly winters and warm summers. A typical July afternoon reaches 85°, a January night drops to 16°, and about 25 inches of snow falls in a normal winter.

25″snow a winter

Typical low → high °F

Winter19–35°

Spring39–61°

Summer62–83°

Fall42–64°

Oct 23

typical first frost

Apr 20

typical last frost

+1.5°

vs. the 20th-century average

NOAA U.S. Climate Normals, 1991–2020Full climate →

Housing

A typical Seneca home is worth about $258K

The typical Seneca home is worth about $258,000, up 5.2% in a year, 13% below the Illinois typical home.

$258KZillow home value

Typical home value

Seneca$258K

Illinois$298K

+5.2%

value change, 1 year

homes sold in May

Zillow Home Value Index · Redfin Data CenterHousing market →

Safety

Crime reported in Seneca

Seneca's reported crime rate is below Illinois's. Most reported incidents are property crimes, mainly thefts. 5 violent crimes were reported in 2025.

Violent crime per 1,000 residents

Seneca2.2

Illinois2.6

U.S.3.3

Property crime per 1,000 residents

Seneca8.3

Illinois15.6

U.S.15.5

violent crimes reported in 2025

property crimes reported in 2025

FBI crime data, 2025 · crimes reported to policeFull safety report →

Armour's Warehouse · National Register of Historic Places

Seneca’s story

172 years in pictures

1 places on the National Register of Historic Places.

1854Seneca is settled

Explore the history →

About Seneca

Village in Illinois, United States

Seneca is a village in LaSalle and Grundy counties in the U.S. state of Illinois. The population was 2,353 at the 2020 census, down from 2,371 at the 2010 census. The LaSalle County portion of Seneca is part of the Ottawa, IL Micropolitan Statistical Area, while the small portion that lies in Grundy County is part of the Chicago metropolitan area.

From Wikipedia, licensed CC BY-SA 4.0 · facts via Wikidata (CC0)