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LaSalle County, Illinois

LaSalle County profile, demographic data, and geographic information.

LaSalle County is a county located in Illinois, United States of America. As of official census estimates, it has a reported population of 107,773. The land area covers 1,135.12 sq mi. [1]

Local Government Administration U.S. Census Bureau GMAF

County Of Lasalle County
Official Title: Chairman
Address: 707 E ETNA RD, ROOM 245, OTTAWA IL 61350-1047

Demographics & Population

Demographic Metric Estimate / Count Margin of Error Survey Period / Source
Total Population (2025 PEP Estimate) 107,773 — 2025 / Census
Median Age 42.2 yrs ±0.3 2020-2024 / Census ACS 5-Year 2024
Total Households 45,373 ±562 2020-2024 / Census ACS 5-Year 2024
Source: U.S. Census Bureau (PEP, ACS 5-Year).

Housing & Real Estate Profile

Housing Metric Estimate / Value Margin of Error
Total Housing Units 49,843 ±57
Occupied Housing Units 45,373 ±562
Vacant Housing Units 4,470 ±549
Median Home Value $161,900 ±$2,651
Median Gross Rent $928 ±$24
Source: U.S. Census Bureau ACS 5-Year (2020-2024).

Economy & Workforce

Economic Metric Estimate / Value Margin of Error
Median Household Income $73,045 ±$2,890
Per Capita Income $39,375 ±$1,283
Poverty Rate 13.9% ±1.3%
Population Below Poverty Level 14,674 ±1,322
Unemployment Rate 5.4% ±0.7%
Civilian Labor Force, Employed 51,486 ±952
Broadband Internet Rate 87.4% ±1.3%
Source: U.S. Census Bureau ACS 5-Year (2020-2024).

Climate & Weather Observations

NOAA Monthly Climate Normals

Observation Station: Climate data reflects NOAA 1991–2020 standard normals recorded at OTTAWA 5SW, IL US, located 1.6 miles from LaSalle County. Local microclimates, topography, and elevation may cause municipal conditions to differ.
Month High (°F) Low (°F) Mean (°F) Precip (in) Snow (in)
January 30.7° 15.2° 22.9° 1.78" 9.2"
February 35.1° 18.9° 27.0° 1.54" 5.2"
March 47.6° 29.0° 38.3° 2.29" 3.3"
April 61.2° 39.4° 50.3° 3.53" 0.4"
May 71.7° 50.9° 61.3° 4.48" 0.0"
June 79.9° 60.5° 70.2° 4.40" 0.0"
July 82.9° 64.4° 73.7° 3.63" 0.0"
August 81.6° 62.3° 71.9° 3.72" 0.0"
September 76.4° 54.2° 65.3° 3.23" 0.0"
October 64.0° 42.6° 53.3° 3.10" 0.0"
November 48.5° 31.5° 40.0° 2.50" 0.8"
December 35.9° 21.1° 28.5° 1.99" 4.8"
Source: NOAA U.S. Climate Normals (1991–2020).

Local Weather Forecast

Weather forecast data is currently unavailable in the local cache.

Sources & Data Provenance

  1. Geographic Classification & Identifiers: U.S. Census Bureau Gazetteer (2026) and TIGER/Line Shapefiles. GEOID: 17099. • Official Source Dataset →
  2. Socioeconomic & Housing Metrics: U.S. Census Bureau American Community Survey (ACS) 5-year estimates and Population Estimates Program (PEP). Margin of Error (MOE) intervals are reported where published; suppressed values are never estimated or replaced with false zeros.
  3. Civic Directory Datasets: Centers for Medicare & Medicaid Services (CMS Hospital Directory), National Center for Education Statistics (NCES IPEDS Postsecondary Directory), and Institute of Museum and Library Services (IMLS Public Libraries Survey). Airport landing facilities are provided by airport-data.com.
  4. Weather & Climate Observations: National Oceanic and Atmospheric Administration (NOAA) U.S. Climate Normals 1991–2020 and National Weather Service (NWS) point forecasts.