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Monroe County, IL Demographics

Monroe County, IL is the 40th most populous of 102 counties in Illinois, with 34,962 residents across 385 square miles. That is about 91 people per square mile.

At the 2020 census

Population 34,962
Land area 385 sq mi
Density 91 / sq mi

Data: 2020 Census · American Community Survey 2024

How Monroe County compares to the US

We're computing this county's comparison table — check back shortly. Population, land area, and density above are already exact.

Central Location: Monroe County, IL

Measured from the county's main population center using 2020 census blocks.

We're computing the drive-time and radius areas around Monroe County, IL — check back shortly. Meanwhile you can drop a pin anywhere in the radius tool.

Census tracts in Monroe County, IL

Name Population Sq mi Per sq mi
Census Tract 6004.01 7,144 23.7 302
Census Tract 6005.01 6,872 76.5 90
Census Tract 6001.02 4,892 39.3 125
Census Tract 6004.02 4,880 63.7 77
Census Tract 6001.04 4,315 2.6 1,638
Census Tract 6001.03 3,687 3.3 1,131
Census Tract 6005.02 3,172 176.3 18

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About this page

This page shows demographics for a US county from the 2020 census and the American Community Survey: population, land area, density, urban share, and how the county compares to national averages for income, housing, age, and more.

Counties subdivide into census tracts, listed below with their populations. The drive-time and radius tables measure the population around the county's main population center.

Read how BlockAtlas computes population within an area →