Illinois Grundy County LaSalle County

Seneca

A village in LaSalle County, Illinois — population 2,217 as of 2020.

Open the map Official city site

This Afternoon 77°F Scattered Rain Showers48% precip
Tonight 50°F Scattered Rain Showers then Patchy Fog31% precip
Monday 77°F Patchy Fog then Mostly Sunny3% precip
Monday Night 69°F Partly Cloudy then Chance Showers And Thunderstorms27% precip

In and around Seneca

Seneca changes faster than we can keep up.

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Seneca by the numbers

Population 2,217Population figure, 2020
Households & income
Area
6.21 sq mi (16.08 km²), 0.37 sq mi water
Median age
35.5
Households
907
Persons per household
2.7
Median household income
$86,830
Median house value
$227,500
2020–2024 ACS
Municipal office
Office
VILLAGE TREAS
Address
340 N. CASH, SENECA, IL 61360
Municipal record
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