ZIP codes in Chickasaw County
10 ZIPs touch Chickasaw County, Iowa. The blue dashed line is the county border; orange ZIPs reach into it.
10
ZIP codes
8
cross the county line
25,968
people in these ZIPs
99
counties in IA
Most people
Chickasaw County ZIP list
More counties in Iowa
- Calhoun County15
- Carroll County17
- Cass County13
- Cedar County18
- Cerro Gordo County18
- Cherokee County15
- Clarke County9
- Clay County17
- Clayton County24
- Clinton County24
- Crawford County21
- Dallas County25
Questions people actually ask
How many ZIP codes are in Chickasaw County, Iowa?
10 ZIP codes reach into Chickasaw County, including 1 PO Box or single-address ZIPs placed by the town they serve. 8 of them are only partly in the county and also cover a neighboring county.
Which ZIP code in Chickasaw County has the most people?
50616 (Charles City) has about 9,358 residents, the most of any ZIP touching Chickasaw County, in the Census Bureau’s ACS 2020–2024 estimates.
Can a ZIP code be in Chickasaw 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 Chickasaw 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