Note: As defined by the US Census Bureau, a city's official boundaries often extend miles beyond the city itself and may even cross county lines. As such, several thousand US cities officially exist in two or more counties (and therefore appear on multiple counties' lists of cities.)
City | Rank | 2024 Pop. | 2020 Pop. | Change | Density (/mi²) | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Lewistown | 1 | 6,208 | 5,971 | 0.96% | 1,085 | 5.7 | City |
| Lewistown Heights | 2 | 499 | 312 | 1.22% | 212 | 2.4 | CDP |
| Denton | 3 | 213 | 208 | 0.47% | 299 | 0.7 | Town |
| Moore | 4 | 204 | 195 | 0.99% | 699 | 0.3 | Town |
| Winifred | 5 | 175 | 170 | 0.57% | 334 | 0.5 | Town |
| Roy | 6 | 172 | 120 | 2.38% | 51 | 3.4 | CDP |
| Grass Range | 7 | 116 | 112 | 0.87% | 829 | 0.1 | Town |
| Fords Creek Colony | 8 | 62 | 43 | 8.77% | 356 | 0.2 | CDP |
| Ayers Ranch Colony | 9 | 46 | 66 | 9.52% | 105 | 0.4 | CDP |
| Coffee Creek | 10 | 44 | 0 | 7.32% | 120 | 0.4 | CDP |
| King Ranch Colony | 11 | 22 | 69 | 4.76% | 20 | 1.1 | CDP |
| Deerfield Colony | 12 | 20 | 0 | 11.11% | 35 | 0.6 | CDP |
| Warm Spring Creek | 13 | 18 | 0 | 12.5% | 42 | 0.4 | CDP |
| Danvers | 14 | 10 | 10 | 0% | 37 | 0.3 | CDP |
Note: City markers shown outside the county boundary mean that a part of the city extends into this county, but is primarily located in an adjacent county.
Lewistown is the largest city in Fergus County.
Danvers is the smallest city in Fergus County.
There are 14 cities in Fergus County, Montana.