ZIP codes in Hardin County
6 ZIPs touch Hardin County, Illinois. The blue dashed line is the county border; orange ZIPs reach into it.
6
ZIP codes
3
cross the county line
6,213
people in these ZIPs
102
counties in IL
Most people
Hardin County ZIP list
More counties in Illinois
- Fulton County24
- Gallatin County9
- Greene County14
- Grundy County16
- Hamilton County13
- Hancock County21
- Henderson County17
- Henry County24
- Iroquois County28
- Jackson County23
- Jasper County15
- Jefferson County18
Questions people actually ask
How many ZIP codes are in Hardin County, Illinois?
6 ZIP codes reach into Hardin County, including 1 PO Box or single-address ZIPs placed by the town they serve. 3 of them are only partly in the county and also cover a neighboring county.
Which ZIP code in Hardin County has the most people?
62938 (Golconda) has about 2,622 residents, the most of any ZIP touching Hardin County, in the Census Bureau’s ACS 2020–2024 estimates.
Can a ZIP code be in Hardin County and another county?
Yes. ZIP codes follow mail routes, not county lines. Rows marked with a percentage show how much of that ZIP’s land is in Hardin County. For one address, pin the exact spot on the ZIP finder to see its county.
Where does this list come from?
ZIP areas and their county overlaps come from the Census Bureau’s 2020 ZIP Code Tabulation Area to county relationship file. PO Box ZIPs have no area, so each is placed in the county of the ZIP area nearest the town it serves.
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Updated 2026-11-10 · Where the data comes from