| Zip Code | City | Population ↓ |
|---|---|---|
| 50595 | Webster City | 8,823 |
| 50130 | Jewell | 1,567 |
| 50249 | Stratford | 1,404 |
| 50075 | Ellsworth | 749 |
| 50246 | Stanhope | 716 |
| 50271 | Williams | 623 |
| 50034 | Blairsburg | 437 |
| 50132 | Kamrar | 389 |
| 50231 | Randall | 157 |
The data shown reflect ZCTAs from the US Census. As of 2024, there are 9 ZCTAs in Hamilton County, Iowa (US Census).