Marengo - Seneca, Chicagoland, IL demographics:
population, income, and more

Total population
12,886
0.6% year-over-year change
Median household income
$98,451/yr
4.5% year-over-year change
Housing units
5,121
1.3% year-over-year change

Marengo - Seneca population

How many people live in Marengo - Seneca

Marengo - Seneca is home to 12,886 residents, according to the most recent Census data. Gender-wise, 51% of Marengo - Seneca locals are male, and 49% are female.

Total population
12,886
0.6% year-over-year change
Gender ratio
Male
51%
6,571
Female
49%
6,315
Value Percent YoY change
Male 6,571 51% 1.8%
Female 6,315 49% -0.7%
A higher population often means more rental variety and livelier areas. The gender balance—how many men live here compared to women—can reveal a lot about the community and the lifestyles of its residents. Use this info to get a sense of the area's pace and personality.

Age demographics

The median age in Marengo - Seneca is 40, with the population distributed as follows: about 17.1% are children under 15, then 14.5% are in the 15 to 24 age group. Adults between 25 and 44 make up 23.9% of the population, while another 26.3% fall into the 45 to 64 bracket. Finally, around 18.2% are 65 or older.

Median age
39.7
Age breakdown
Under 15
17.1%
15 to 24
14.5%
25 to 44
23.9%
45 to 64
26.3%
Over 65
18.2%
Value Percent YoY change
Under 15 2,200 17.1% -8.1%
15 to 24 1,863 14.5% 7.5%
25 to 44 3,080 23.9% -1.5%
45 to 64 3,392 26.3% 3.2%
Over 65 2,351 18.2% 3.5%
The age composition helps you get insight into who lives in the area. A younger population might mean a more active, fast-paced vibe, while an older one could suggest a quieter, slower lifestyle. If there's a balanced makeup, you’re likely to find a variety of services, housing types, and community spaces that cater to different life stages.

Racial makeup

In Marengo - Seneca, 90.1% of the population are US-born citizens, while 4.4% have gained naturalized citizenship. At the same time, 5.6% of residents are non-citizens. As for race, 79.8% of locals are Caucasian, 1.3% are African American and 1.4% have Asian roots. There’s also a share of 13.1% that includes residents with two or more races.

Citizenship
U.S.-born citizens
90.1%
Non-U.S.-born citizens
4.4%
Non-citizens
5.6%
Value Percent YoY change
U.S.-born citizens 11,608 90.1% -0.8%
Non-U.S.-born citizens 560 4.4% 13.8%
Non-citizens 718 5.6% 16.6%
Racial breakdown
White
79.8%
Black or African American
1.3%
American Indian and Alaska Native
0.7%
Asian
1.4%
Native Hawaiian and other Pacific Islander
0%
Two or more races
13.1%
Other
3.6%
Value Percent
White 10,289 79.8%
Black or African American 171 1.3%
American Indian and Alaska Native 92 0.7%
Asian 182 1.4%
Native Hawaiian and other Pacific Islander 3 0%
Two or more races 1,684 13.1%
Other 465 3.6%

Households in Marengo - Seneca

A peek inside Marengo - Seneca households

Marengo - Seneca has 4,951 households, with an average of 3 members in each. Of these, 68.5% are families, while the remaining 31.5% are made up of individuals living alone or with non-relatives, such as roommates.

Households stats

Total households
4,951
2.1% year-over-year change
Average people per household
3
Non-family households
1,559
Family households
3,392
Value Percent YoY change
Non-family households 1,559 31.5% 4.8%
Family households 3,392 68.5% 0.9%
The mix between family and non-family households gives a glimpse into daily life. A higher percentage of families might mean more parks and schools, while more non-family setups can mean flexible housing and diverse living styles. For renters, this can signal what kinds of homes are common and can help you figure out if the area matches your lifestyle.

Housing in Marengo - Seneca

The housing landscape of Marengo - Seneca

Marengo - Seneca's housing consists of 5,121 units, with 71% being detached single-family homes ideal for those wanting space. Attached options, including duplexes and townhouses, make up 9.2% and offer a more compact, shared living style. Then there are the multifamily buildings in the area, and for those seeking flexibility, non-traditional options like mobile homes account for 2% of the housing landscape.

Housing units
5,121
1.3% year-over-year change
Housing types
Value Percent
1 unit, detached 3,637 71%
1 unit, attached 470 9.2%
2 units 130 2.5%
3 or 4 units 223 4.4%
5 to 9 units 332 6.5%
10 to 19 units 84 1.6%
20 to 49 units 74 1.4%
50 or more units 65 1.3%
Mobile home 105 2%
Homes built since 2020
28
64.7% year-over-year change

The age of buildings in Marengo - Seneca

In Marengo - Seneca, the median construction year is 1979. About 17.1% of homes were built before the 1940s, with another 2.5% going up by 1949. Most development happened in the second half of the 20th century. Then, 18.7% of homes were added from 2000 to 2009, 4.8% between 2010 and 2019, and 0.6% are part of the newest wave of development.

Construction year breakdown by decade
Value Percent YoY change
Built in 1939 or earlier 876 17.1% -2.8%
Built between 1940 and 1949 127 2.5% 60.8%
Built between 1950 and 1959 319 6.2% -5.6%
Built between 1960 and 1969 431 8.4% -8.3%
Built between 1970 and 1979 637 12.4% 4.6%
Built between 1980 and 1989 676 13.2% -6.1%
Built between 1990 and 1999 823 16.1% 4.3%
Built between 2000 and 2009 958 18.7% 1.1%
Built between 2010 and 2019 245 4.8% 33.9%
Built in 2020 or later 28 0.6% 64.7%
As a renter, knowing when homes were built helps you understand the potential condition and design of rental units. Newer builds may have more contemporary layouts, while older homes can offer character or larger lots, depending on the area.

Marengo - Seneca occupancy rates

Out of the 4,951 occupied housing units in Marengo - Seneca, 75.8% are owner-occupied, while 24.2% are lived in by tenants. Meanwhile, 3.3% of all homes on the local market sit vacant.

Occupied housing units
4,951
2.1% year-over-year change
Occupancy breakdown
Renter occupied
1,196
Owner occupied
3,755
Value Percent YoY
change
Renter occupied 1,196 24.2% 4.0%
Owner occupied 3,755 75.8% 1.6%
Unoccupied housing units
3.3%
Unoccupied housing units refer to homes that are currently without residents—whether they're waiting for renters or owners, used seasonally, or simply unclaimed. A higher share of empty homes may mean more housing availability, while a low number can reflect a tighter market with more competition. This, along with the renter-vs.-owner mix, helps paint a clearer picture of what types of housing and services are likely to be available in the area.

Marengo - Seneca housing costs

Housing costs in Marengo - Seneca come to a median of $1,433 per month, while tenants specifically pay a median gross rent of $1,215.

Median housing costs per month
$1,433/month
This figure sums up typical monthly housing costs for all households in the area. If you own, it includes mortgage payments in addition to property taxes, insurance and HOA fees. If you rent, it accounts for rent plus extras like utilities. It’s useful for seeing how local living expenses stack up compared to other places.
Median gross rent in Marengo - Seneca
$1,215/month
Gross rent gives a more complete look at what renters actually pay, including not just base rent, but also utilities and fees. It’s a key number for evaluating rental affordability in your area of interest and understanding how it compares to nearby locations.

Education in Marengo - Seneca

Marengo - Seneca education at a glance

About 35.9% of the population in Marengo - Seneca went to high school, while 25.2% pursued college studies. Another 8.9% earned an associate degree and 18.6% hold a bachelor’s. Meanwhile, 8.2% went even further, earning a master’s or doctorate.

Education level
Value Percent YoY change
No high school 317 3.2% 1.0%
High school diploma 3,600 35.9% 4.8%
College diploma 2,528 25.2% 5.0%
Associate degree 897 8.9% 5.0%
Bachelor's degree 1,861 18.6% -0.9%
Graduate degree 827 8.2% -7.9%
A community’s education mix can offer insights into the local economy and housing market. Higher levels of education often align with more job opportunities and stable incomes, which can increase demand for homes and influence both rent prices and rental availability.

Income in Marengo - Seneca

How much people earn in Marengo - Seneca

The average annual household income in Marengo - Seneca was $111,603 in 2024, the most recent annual data available, according to the U.S. Census Bureau. This marked a +1.5% change from the previous year. At the same time, the median income stood at $98,451, reflecting a +4.5% shift over the same period.

Average household income in Marengo - Seneca
$111,603/year
1.5% year-over-year change
Median household income in Marengo - Seneca
$98,451/year
4.5% year-over-year change

Marengo - Seneca income by age

In Marengo - Seneca, households led by residents aged 25 to 44 — usually in the early to mid stages of their careers — have a median income of $111,310. Those with someone between 45 and 64 in charge, often well established professionally, earn $115,931 overall. Younger households, where the main provider is under 25 and just starting out, report a median income of $98,707, while those led by someone over 65, many of whom may be retired, have about $70,945 in earnings. Overall, 92.3% of the locals in this community live above the poverty line.

Income breakdown by age
Value YoY change
Under 25 $98,707 3.6%
25 - 44 $111,310 2.0%
45 - 64 $115,931 -10.9%
Over 65 $70,945 3.0%
Above poverty level
11,582
Below poverty level
961
Value Percent YoY
change
Above poverty level 11,582 92.3% 1.7%
Below poverty level 961 7.7% -5.4%

Employment in Marengo - Seneca

Workforce and job types in Marengo - Seneca

73.2% of the working population are employed in professional or administrative positions, while 26.8% are in hands-on or service-based jobs. Also, 9.1% run their own businesses, 71.5% are employed by private companies, and 14% work in the public sector.

Workforce demographics

White collar
4,812
Blue collar
1,763
Value Percent YoY change
White collar 4,812 73.2% 0.5%
Blue collar 1,763 26.8% -1.9%
Employer type
Self employees
9.1%
Private companies
71.5%
Governmental workers
14%
Not for profit companies
5.4%
Value Percent YoY change
Self employees 601 9.1% 10.5%
Private companies 4,703 71.5% -1.2%
Governmental workers 918 14% -3.0%
Not for profit companies 354 5.4% 5.7%

Transportation in Marengo - Seneca

How people get around in Marengo - Seneca

Commuting methods vary: 97.9% of residents travel by personal vehicle and 1.3% prefer to walk, while the remaining share relies on public transit or on two wheelers to get from A to B.

Means of transportation
Value Percent YoY change
Car 5,545 97.9% -1.8%
Taxicab 8 0.1% 14.3%
Bus or trolleybus 6 0.1% 20.0%
Railroad 23 0.4% 9.5%
Ferryboat 2 0% N/A
Motorcycle 3 0% 50.0%
Bicycle 1 0% -87.5%
Walk 75 1.3% -2.6%
Understanding how locals get to work can help you plan your own routine. High car usage might mean you’ll need a vehicle, while strong public transit or walkability could save you the hassle. Commute times also play a big role in quality of life—shorter trips can give you more time for the things you enjoy.

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FAQs about Marengo - Seneca demographics 

What is the total population of Marengo - Seneca?

Marengo - Seneca has a total population of 12,886 residents, according to the latest release from the U.S. Census Bureau: the 2019-2023 American Community Survey (ACS) 5-year estimates. This figure changed by +0.6% compared to a year ago.

What is the gender ratio in Marengo - Seneca?

The gender ratio in Marengo - Seneca is as follows:
  • 51% males (6,571 residents)
  • 49% females (6,315 residents)

What is the median age in Marengo - Seneca?

The median age in Marengo - Seneca is 39.7.

What is the age distribution of the population in Marengo - Seneca?

The age distribution in Marengo - Seneca is as follows:
  • Under 15: 17.1% (2,200 residents)
  • Ages 15-24: 14.5% (1,863 residents)
  • Ages 25-44: 23.9% (3,080 residents)
  • Ages 45-64: 26.3% (3,392 residents)
  • Over 65: 18.2% (2,351 residents)

What is the racial and ethnic makeup of Marengo - Seneca?

The racial and ethnic makeup of Marengo - Seneca is as follows:
  • White: 79.8% (10,289 residents)
  • Black or African American: 1.3% (171 residents)
  • American Indian and Alaska Native: 0.7% (92 residents)
  • Asian: 1.4% (182 residents)
  • Native Hawaiian and Other Pacific Islander: 0% (3 residents)
  • Two or More Races: 13.1% (1,684 residents)
  • Other: 3.6% (465 residents)

What percentage of the population in Marengo - Seneca are U.S.-born citizens?

U.S.-born citizens represent 90.1% of the population in Marengo - Seneca.

How many housing units are there in Marengo - Seneca?

There are 5,121 housing units in Marengo - Seneca, reflecting a +1.3% change compared to the previous year, according to the latest data from the U.S. Census Bureau.

How many households are in Marengo - Seneca and what is the average household size?

Marengo - Seneca has a total of 4,951 households, with an average of 3 people in each.

What is the median household income in Marengo - Seneca?

Marengo - Seneca has a median household income of $98,451, representing a +4.5% shift from the previous year, according to the U.S. Census Bureau.

What is the job market overview for Marengo - Seneca?

Here’s a detailed breakdown of the local job market:

Job types:
  • White-collar workers: 73.2% (4,812 residents)
  • Blue-collar workers: 26.8% (1,763 residents)

Places of employment:
  • Self-employed: 9.1% (601 residents)
  • Private companies: 71.5% (4,703 residents)
  • Governmental workers: 14% (918 residents)
  • Not-for-profit companies: 5.4% (354 residents)

Data source & methodology

The demographic data on this page was sourced from the latest U.S. Census Bureau release—the 2019–2023 American Community Survey (ACS) 5-year estimates.

The information, issued annually, is compiled and published by the Point2Homes Research Team as soon as new data becomes available.

No representation, guarantee, or warranty is made concerning the accuracy or completeness of modified or aggregated information for particular areas.

Page last updated: September 2025