ZIP CodesZIP codes in O'Brien County, Iowa
O'Brien County, Iowa has 8 ZIP codes in this list, from 51009 to 51346. They cover 8 places, among them Calumet, Paullina, Sutherland and Sheldon.
| ZIP code | Place | Land area (sq mi) | Map point |
|---|---|---|---|
| 51009 | Calumet | 0.3 | 42.944, -95.552 |
| 51046 | Paullina | 93.3 | 42.970, -95.708 |
| 51058 | Sutherland | 85.7 | 42.983, -95.481 |
| 51201 | Sheldon | 116 | 43.181, -95.840 |
| 51231 | Archer | 24.2 | 43.118, -95.742 |
| 51245 | Primghar | 77.4 | 43.076, -95.653 |
| 51248 | Sanborn | 79.2 | 43.189, -95.662 |
| 51346 | Hartley | 146 | 43.180, -95.482 |
The ZIP code areas of O'Brien County add up to about 622 square miles of land (1,610 sq km) as the Census Bureau draws them. The largest is 51346 (Hartley), with 146 square miles.
Using these codes
- In an address, the ZIP code comes last, after the city and the two-letter state: Calumet, IA 51009.
- Tap a ZIP code to open it in the look-up, with a copy button for the address line.
- A code can cross a county line, and one town can have several codes. The table shows the main place of each code.
- "No area" means the Census Bureau draws no area for that code. Such codes are usually for post office boxes or a single building.
Places and counties: GeoNames. Areas: U.S. Census Bureau, 2024 ZIP Code Tabulation Areas. Checked in November 2026. This site is not connected with the United States Postal Service; for mailing, confirm the address with USPS.