ZIP codes in Hardin County
15 ZIPs touch Hardin County, Iowa. The blue dashed line is the county border; orange ZIPs reach into it.
15
ZIP codes
10
cross the county line
19,361
people in these ZIPs
99
counties in IA
Most people
Hardin County ZIP list
More counties in Iowa
- Fremont County11
- Greene County14
- Grundy County17
- Guthrie County18
- Hamilton County15
- Hancock County13
- Harrison County15
- Henry County12
- Howard County9
- Humboldt County17
- Ida County12
- Iowa County22
Questions people actually ask
How many ZIP codes are in Hardin County, Iowa?
15 ZIP codes reach into Hardin County, including 2 PO Box or single-address ZIPs placed by the town they serve. 10 of them are only partly in the county and also cover a neighboring county.
Which ZIP code in Hardin County has the most people?
50126 (Iowa Falls) has about 6,368 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.
Keep exploring
Updated 2026-11-10 · Where the data comes from