6 cities
| City | Rank | 2026 Pop. ↓ | 2020 Pop. | Annual Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Sedalia | 1 | 22,594 | 21,742 | 0.63% | 1,503 | 15 | City |
| La Monte | 2 | 1,011 | 1,005 | 0.1% | 932 | 1 | City |
| Green Ridge | 3 | 663 | 470 | 5.07% | 1,545 | 0 | City |
| Smithton | 4 | 503 | 506 | 0% | 1,671 | 0 | City |
| Houstonia | 5 | 195 | 194 | 0% | 985 | 0 | City |
| Hughesville | 6 | 153 | 149 | 0.66% | 1,319 | 0 | Village |
Sedalia is the largest city in Pettis County, with a population of 22,594.
Hughesville is the smallest city in Pettis County, with a population of 153.
There are 6 cities in Pettis County, Missouri.