ZIP codes in Louisa County
13 ZIPs touch Louisa County, Iowa. The blue dashed line is the county border; orange ZIPs reach into it.
13
ZIP codes
10
cross the county line
48,362
people in these ZIPs
99
counties in IA
Most people
Louisa County ZIP list
More counties in Iowa
- Johnson County26
- Jones County17
- Keokuk County21
- Kossuth County20
- Lee County14
- Linn County38
- Lucas County9
- Lyon County12
- Madison County15
- Mahaska County20
- Marion County19
- Marshall County21
Questions people actually ask
How many ZIP codes are in Louisa County, Iowa?
13 ZIP codes reach into Louisa County. 10 of them are only partly in the county and also cover a neighboring county.
Which ZIP code in Louisa County has the most people?
52761 (Muscatine) has about 29,474 residents, the most of any ZIP touching Louisa County, in the Census Bureau’s ACS 2020–2024 estimates.
Can a ZIP code be in Louisa 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 Louisa 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