Monmouth city, Illinois
Official LSAD Designation: Monmouth city • Census GEOID: 1750010
• Warren County
Monmouth city is an incorporated city in Warren County, Illinois. According to official records from the Census (2025), Monmouth city had an estimated population of 8,599 residents. Official Census Bureau geographic records classify this community under LSAD designation Monmouth city (GEOID 1750010).
Local Government Administration U.S. Census Bureau GMAF
City Of Monmouth
Municipal
Official Title:
City Administrator
Address:
100 E BROADWAY, MONMOUTH IL 61462-5704
County Of Warren
County
Official Title:
Warren County Clerk/recorder
Address:
100 W BROADWAY, MONMOUTH IL 61462-1797
Civic & Statistical Snapshot
| Category | Estimate | Survey Period / Source |
|---|---|---|
| Total Population | 8,599 | 2025 |
| Median Household Income | $61,138 | 2020-2024 |
| Median Home Value | $86,800 | 2020-2024 |
| Land Area | 4.25 sq mi | Gazetteer (2026) |
| Civic & Public Services | Hospitals, Libraries, Colleges | CMS / IMLS / IPEDS |
| Schools & Districts | NCES Directory Listings | Provided by k12guides.com |
| Nearby Airports | Landing Facilities | Provided by airport-data.com |
| Climate & Weather | NOAA 30-Year Normals | 1991–2020 |
Source: U.S. Census Bureau (PEP, ACS 5-Year).