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zipcodes.pro — CITY/IL/SENECA

Seneca ZIP code, Illinois

The ZIP code for Seneca, IL is 61360, and its area code is 815.

USPS city name
1 ZIP code
Overlapping the city
2 more
Population
2,450
Area code
815

Mail addressed to Seneca uses the ZIP code above. 2 more ZIP codes cover part of the city but are addressed as somewhere else; they are listed separately below.

Seneca in numbers

About 2,450 people live in Seneca, in 907 households. The median household income is $86,830 a year, 4% above the Illinois median of $83,390 (US: $80,734). The median owner-occupied home is valued at $227,500 (14% below the Illinois median), and median gross rent is $1,149 a month. The median age is 35.5; 14.9% of adults 25 and over hold a bachelor's degree or higher (37.8% across Illinois); the average commute takes 26 minutes.

Population2,450Seneca2,450
Households907Seneca907
Median age35.5Seneca35.5Illinois39.0US 38.9
Median household income$86,830Seneca$86,830Illinois$83,390US $80,734
Median home value$227,500Seneca$227,500Illinois$263,300US $332,700
Median gross rent$1,149Seneca$1,149Illinois$1,274US $1,413
Bachelor's degree or higher14.9%Seneca14.9%Illinois37.8%US 35.7%
Mean commute26.2 minSeneca26.2 minIllinois27.8 minUS 26.4 min
Population density395 / sq miSeneca395 / sq mi

U.S. Census Bureau, American Community Survey 2020–2024 5-year estimates, for the census place Seneca village. Survey estimates carry margins of error, wider for small places. Sources and methods.

ZIP codes addressed as Seneca

ZIP codes with the USPS city name Seneca
ZIP City Type Population Median income Median home
61360 Seneca , IL Standard 3,610 $95,093 $258,200

Other ZIP codes overlapping Seneca

These ZIP codes cover part of Seneca but are addressed as somewhere else.

ZIP codes overlapping Seneca
ZIP City Type Population Median income Median home
60450 Morris , IL Standard 20,783 $81,777 $275,500
61341 Marseilles , IL Standard 7,692 $72,530 $200,900

Map of Seneca ZIP codes

61360

The ZIP codes of Seneca, IL, shaded. Outlines are Census ZIP Code Tabulation Areas (2020), which approximate the mail routes; PO-box and single-address codes have no area and are not drawn. Click any area to open its ZIP code.

Towns near Seneca

The nearest larger towns are Marseilles (4,279 people, 3.7 mi), Morris (14,898 people, 11 mi) and Ottawa (18,447 people, 11 mi).

Towns near Seneca
TownPopulationDistance
Marseilles 4,279 3.7 mi
Morris 14,898 11.2 mi
Ottawa 18,447 11.4 mi
Sheridan 2,519 16.0 mi
Streator 12,330 16.6 mi
Dwight 3,872 17.3 mi
Coal City 5,317 17.4 mi
Diamond 2,984 18.9 mi
Minooka 12,891 19.8 mi
Channahon 13,927 20.0 mi
Braidwood 6,062 20.4 mi
Lake Holiday 5,641 22.1 mi
Wilmington 5,494 23.6 mi
Oglesby 3,570 23.7 mi

More nearby: every ZIP code in LaSalle County · Illinois ZIP codes

Cite this page

zipcodes.pro. “Seneca, IL ZIP codes.” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/city/il/seneca

Underlying data is public domain or openly licensed — sources, vintages and licences.