7 cities
| City | Rank | 2026 Pop. ↓ | 2020 Pop. | Annual Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Hamilton | 1 | 6,955 | 6,922 | 0.09% | 183 | 38 | City |
| Winfield | 2 | 4,862 | 4,862 | 0% | 273 | 18 | City |
| Guin | 3 | 2,112 | 2,187 | -0.56% | 141 | 15 | City |
| Hackleburg | 4 | 1,458 | 1,428 | 0.34% | 95 | 15 | Town |
| Bear Creek | 5 | 1,059 | 1,038 | 0.38% | 78 | 14 | Town |
| Brilliant | 6 | 841 | 835 | 0.12% | 79 | 11 | Town |
| Twin | 7 | 358 | 360 | 0% | 106 | 3 | Town |
Hamilton is the largest city in Marion County, with a population of 6,955.
Twin is the smallest city in Marion County, with a population of 358.
There are 7 cities in Marion County, Alabama.