17 cities
| City | Rank | 2025 Pop. ↓ | 2020 Pop. | Annual Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Charleston | 1 | 4,406 | 5,053 | -0.92% | 919 | 5 | City |
| Charleston | 2 | 4,406 | 4,609 | -0.92% | 919 | 5 | City |
| East Prairie | 3 | 2,839 | 2,938 | -0.7% | 2,271 | 1 | City |
| East Prairie | 4 | 2,839 | 2,938 | -0.7% | 2,271 | 1 | City |
| Miner | 5 | 889 | 910 | -0.45% | 193 | 5 | City |
| Miner | 6 | 889 | 909 | -0.45% | 193 | 5 | City |
| Bertrand | 7 | 700 | 718 | -0.57% | 850 | 1 | City |
| Bertrand | 8 | 700 | 717 | -0.57% | 850 | 1 | City |
| Wyatt | 9 | 205 | 215 | -0.97% | 175 | 1 | City |
| Wyatt | 10 | 205 | 215 | -0.97% | 175 | 1 | City |
| Whiting | 11 | 190 | 134 | 7.34% | 728 | 0 | CDP |
| Anniston | 12 | 178 | 183 | -0.56% | 455 | 0 | Town |
| Anniston | 13 | 178 | 183 | -0.56% | 455 | 0 | Town |
| Diehlstadt | 14 | 156 | 159 | -0.64% | 2,108 | 0 | Village |
| Diehlstadt | 15 | 156 | 159 | -0.64% | 2,108 | 0 | Village |
| Wilson City | 16 | 74 | 77 | -1.33% | 987 | 0 | Village |
| Wilson City | 17 | 74 | 77 | -1.33% | 987 | 0 | Village |
Charleston is the largest city in Mississippi County, with a population of 4,406.
Wilson City is the smallest city in Mississippi County, with a population of 74.
There are 17 cities in Mississippi County, Missouri.