Plymouth County, Iowa ZIP codes
11 ZIP codes are in Plymouth County, plus 4 that cross in from neighboring counties. It's part of the Le Mars, IA micro area.
- ZIP codes
- 11
- Population in these ZIPs
- 34,178
- Avg. median income
- $82,100population-weighted
- Cities & towns
- 10
Click anywhere on the map to see which ZIP code it's in.
ZIP codes in Plymouth County
| ZIP code | City | Population | Median income | Typical home value |
|---|---|---|---|---|
| 51001 | Akron | 2,342 | $75,404 | $235,700 |
| 51008 | Brunsville | 210 | $45,000 | $129,200 |
| 51024 | Hinton | 2,081 | $114,219 | $390,900 |
| 51028 | Kingsley | 2,191 | $78,000 | $255,000 |
| 51031 | Le Mars | 12,808 | $76,525 | $278,500 |
| 51038 | Merrill | 1,449 | $95,893 | $286,300 |
| 51045 | Oyens | 66 | $113,750 | $170,000 |
| 51050 | Remsen | 2,962 | $92,500 | $278,500 |
| 51062 | Westfield | 503 | — | $356,000 |
| 51108 | Sioux City | 5,960 | $81,205 | $252,600 |
| 51109 | Sioux City | 3,606 | $79,034 | $175,800 |
ZIP codes partly in Plymouth County
These ZIP codes are mostly in a neighboring county but cover part of Plymouth County.
| ZIP code | City | County | Population | Median income | Typical home value |
|---|---|---|---|---|---|
| 51022 | Granville | O'Brien County | 960 | $96,505 | $274,900 |
| 51027 | Ireton | Sioux County | 1,280 | $100,893 | $281,000 |
| 51035 | Marcus | Cherokee County | 1,627 | $79,338 | $184,200 |
| 51048 | Pierson | Woodbury County | 435 | $83,158 | $167,900 |
Population and median household income: ACS 2020–2024 5-year estimates. Typical home value: Zillow Home Value Index (September 2026) where available, otherwise the ACS median owner-reported value. "PO Box" marks ZIP codes with no delivery area of their own. Methodology
Cities and towns in Plymouth County
Nearby counties
Frequently asked questions
How many ZIP codes are in Plymouth County, Iowa?
11 ZIP codes are mainly in Plymouth County, and 4 more ZIP codes from neighboring areas reach partly into it.
What cities are in Plymouth County?
ZIP codes in Plymouth County use the city names Akron, Brunsville, Hinton, Kingsley, Le Mars, Merrill, Oyens, Remsen, Sioux City and Westfield.
What metro area is Plymouth County in?
Plymouth County is part of the Le Mars, IA micropolitan statistical area.