| Zip Code | City | Population ↓ |
|---|---|---|
| 97914 | Ontario | 19,713 |
| 97913 | Nyssa | 5,520 |
| 97918 | Vale | 4,567 |
| 97901 | Adrian | 954 |
| 97910 | Jordan Valley | 645 |
| 97906 | Harper | 360 |
| 97917 | Riverside | 50 |
| 97903 | Brogan | 48 |
| 97911 | Juntura | 42 |
| 97920 | Westfall | 34 |
| 97908 | Ironside | 30 |
| 97909 | Jamieson | 24 |
| 97902 | Arock | 17 |
The data shown reflect ZCTAs from the US Census. As of 2025, there are 13 ZCTAs in Malheur County, Oregon (US Census).