Postal reference / United States
51102Sioux City, Iowa
ZIP code 51102 is a United States postal code for Sioux City, Iowa. Its county association is Woodbury County. The map reference point is at 42.3684, -96.318.
- State / territory
- Iowa
- Recorded place name
- Sioux City
- County association
- Woodbury
- Estimated coordinate
- 42.3684, -96.318
View on OpenStreetMap - ZIP prefix
- 511 · 9 ZIP codes share it
- Data source
- GeoNames postal reference, snapshot September 26, 2026
GeoNames reference data. County associations may not include every intersecting county, place names are postal names rather than legal boundaries, and coordinates are approximate. This is not address validation.
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Iowa directoryOther ZIP codes in Sioux City, IA
Sioux City has 9 ZIP codes in the reference dataset.
Nearby ZIP code reference points
| ZIP code | Place | State | County association | Miles |
|---|---|---|---|---|
| 51054 | Sergeant Bluff | IA | Woodbury | 2.9 |
| 51052 | Salix | IA | Woodbury | 3.0 |
| 51111 | Sioux City | IA | Woodbury | 3.9 |
| 68731 | Dakota City | NE | Dakota | 7.0 |
| 51106 | Sioux City | IA | Woodbury | 7.0 |
| 51007 | Bronson | IA | Woodbury | 7.4 |
| 68030 | Homer | NE | Dakota | 7.9 |
| 68776 | South Sioux City | NE | Dakota | 8.4 |
Straight-line distance between reference points. Nearby points do not prove that ZIP areas touch.
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