12 cities
| City | Rank | 2025 Pop. ↓ | 2020 Pop. | Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Ennis | 1 | 1,129 | 924 | 3.77% | 1,530 | 0.74 | Town |
| Sheridan | 2 | 803 | 698 | 2.69% | 794 | 1.01 | Town |
| Twin Bridges | 3 | 418 | 335 | 4.24% | 412 | 1.01 | Town |
| McAllister | 4 | 276 | 209 | 6.98% | 122 | 2.27 | CDP |
| Virginia City | 5 | 257 | 219 | 3.21% | 271 | 0.95 | Town |
| Pony | 6 | 142 | 138 | 1.43% | 106 | 1.34 | CDP |
| Alder | 7 | 109 | 93 | 0% | 54 | 2.01 | CDP |
| Silver Star | 8 | 93 | 89 | 8.14% | 202 | 0.46 | CDP |
| Brandon | 9 | 80 | 65 | 6.67% | 181 | 0.44 | CDP |
| Jeffers | 10 | 56 | 17 | 7.69% | 177 | 0.32 | CDP |
| Norris | 11 | 55 | 22 | 7.84% | 164 | 0.34 | CDP |
| Harrison | 12 | 18 | 64 | -30.77% | 103 | 0.17 | CDP |
Ennis is the largest city in Madison County, with a population of 1,129.
Harrison is the smallest city in Madison County.
There are 12 cities in Madison County, Montana.