Alton city, Illinois
Official LSAD Designation: Alton city • Census GEOID: 1701114
• Madison County
Alton city is an incorporated city in Madison County, Illinois. According to official records from the Census (2025), Alton city had an estimated population of 25,013 residents. Official Census Bureau geographic records classify this community under LSAD designation Alton city (GEOID 1701114).
Local Government Administration U.S. Census Bureau GMAF
City Of Alton
Municipal
Official Title:
City Comptroller
Address:
101 E 3RD ST, STE 102, ALTON IL 62002-6239
County Of Madison
County
Official Title:
Auditor
Address:
157 N MAIN ST, RM 382, EDWARDSVILLE IL 62025-1965
Civic & Statistical Snapshot
| Category | Estimate | Survey Period / Source |
|---|---|---|
| Total Population | 25,013 | 2025 |
| Median Household Income | $54,568 | 2020-2024 |
| Median Home Value | $103,700 | 2020-2024 |
| Land Area | 15.63 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).