County · Illinois · United States
Franklin County ZIP codes
15 ZIP codes · 15 cities · FIPS 17055
Key facts
- State
- Illinois (IL)
- FIPS code
- 17055
- Population
- 37,541
- Median household income
- $53,471
- Median age
- 43.4
- Land area
- 408.9 sq mi (1,059.1 km²)
- Population density
- 92 / sq mi
- Area codes
- 618, 730
Cities and ZIP codes in Franklin County (15)
About this page
County figures are Census county-level values (ACS 5-year); the ZIP list shows the ZIPs whose primary county this is — a ZIP on a border can also serve neighbouring counties.
Sources: U.S. Census Bureau (2020 county relationship file, ACS 5-year) · GeoNames. Methodology.