13 ZIP Codes
| Zip Code | City | Population ↓ |
|---|---|---|
| 50158 | Marshalltown | 31,396 |
| 50247 | State Center | 2,004 |
| 50162 | Melbourne | 1,164 |
| 50106 | Gilman | 1,163 |
| 50005 | Albion | 812 |
| 50142 | Le Grand | 720 |
| 50141 | Laurel | 587 |
| 50234 | Rhodes | 559 |
| 50120 | Haverhill | 428 |
| 50148 | Liscomb | 406 |
| 50239 | Saint Anthony | 354 |
| 50051 | Clemons | 224 |
| 50078 | Ferguson | 85 |
The data shown reflect ZCTAs from the US Census. As of 2025, there are 13 ZCTAs in Marshall County, Iowa (US Census).