8 cities
| City | Rank | 2026 Pop. ↓ | 2020 Pop. | Annual Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Montgomery City | 1 | 2,786 | 2,803 | -0.11% | 825 | 3 | City |
| Wellsville | 2 | 1,015 | 988 | 0.5% | 660 | 2 | City |
| Jonesburg | 3 | 859 | 723 | 2.75% | 428 | 2 | City |
| New Florence | 4 | 635 | 637 | 0% | 211 | 3 | City |
| Bellflower | 5 | 341 | 329 | 0.59% | 610 | 1 | City |
| High Hill | 6 | 184 | 186 | 0% | 400 | 0 | City |
| Middletown | 7 | 170 | 170 | 0% | 530 | 0 | Town |
| Rhineland | 8 | 135 | 137 | 0% | 401 | 0 | Town |
Montgomery City is the largest city in Montgomery County, with a population of 2,786.
Rhineland is the smallest city in Montgomery County, with a population of 135.
There are 8 cities in Montgomery County, Missouri.