9 cities
| City | Rank | 2025 Pop. ↓ | 2020 Pop. | Annual Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Madras | 1 | 7,833 | 7,464 | 0.89% | 960 | 8 | City |
| Madras | 2 | 7,833 | 7,488 | 0.89% | 960 | 8 | City |
| Warm Springs | 3 | 2,330 | 2,702 | -1.73% | 55 | 42 | CDP |
| Culver | 4 | 1,686 | 1,602 | 0.96% | 2,426 | 1 | City |
| Culver | 5 | 1,686 | 1,605 | 0.96% | 2,426 | 1 | City |
| Terrebonne | 6 | 1,308 | 1,623 | 0.23% | 1,289 | 1 | CDP |
| Metolius | 7 | 1,039 | 979 | 1.07% | 2,174 | 0 | City |
| Metolius | 8 | 1,039 | 981 | 1.07% | 2,174 | 0 | City |
| Camp Sherman | 9 | 333 | 327 | 2.15% | 106 | 3 | CDP |
Madras is the largest city in Jefferson County, with a population of 7,833.
Camp Sherman is the smallest city in Jefferson County, with a population of 333.
There are 9 cities in Jefferson County, Oregon.