20 ZIP Codes
| Zip Code | City | Population ↓ |
|---|---|---|
| 51106 | Sioux City | 28,592 |
| 51104 | Sioux City | 23,197 |
| 51103 | Sioux City | 16,895 |
| 51105 | Sioux City | 10,415 |
| 51054 | Sergeant Bluff | 5,583 |
| 51039 | Moville | 2,845 |
| 51030 | Lawton | 1,468 |
| 51055 | Sloan | 1,346 |
| 51016 | Correctionville | 1,080 |
| 51052 | Salix | 1,050 |
| 51101 | Sioux City | 1,031 |
| 51026 | Hornick | 910 |
| 51004 | Anthon | 858 |
| 51007 | Bronson | 691 |
| 51019 | Danbury | 448 |
| 51048 | Pierson | 435 |
| 51056 | Smithland | 346 |
| 51044 | Oto | 165 |
| 51015 | Climbing Hill | 45 |
| 51111 | Sioux City | 39 |
The data shown reflect ZCTAs from the US Census. As of 2025, there are 20 ZCTAs in Woodbury County, Iowa (US Census).