| Zip Code | City | Population ↓ |
|---|---|---|
| 59011 | Big Timber | 3,148 |
| 59052 | McLeod | 130 |
| 59033 | Greycliff | 124 |
| 59055 | Melville | 123 |
The data shown reflect ZCTAs from the US Census. As of 2024, there are 4 ZCTAs in Sweet Grass County, Montana (US Census).