19 cities
| City | Rank | 2025 Pop. ↓ | 2020 Pop. | Annual Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Warrensburg | 1 | 20,159 | 19,329 | 0.81% | 2,143 | 9 | City |
| Warrensburg | 2 | 20,159 | 19,351 | 0.81% | 2,143 | 9 | City |
| Whiteman AFB | 3 | 4,510 | 4,092 | 2.97% | 675 | 7 | CDP |
| Knob Noster | 4 | 2,975 | 2,756 | 1.47% | 1,033 | 3 | City |
| Knob Noster | 5 | 2,975 | 2,760 | 1.47% | 1,033 | 3 | City |
| Holden | 6 | 2,334 | 2,206 | 1.08% | 968 | 2 | City |
| Holden | 7 | 2,334 | 2,209 | 1.08% | 968 | 2 | City |
| Leeton | 8 | 553 | 532 | 0.73% | 1,072 | 1 | City |
| Leeton | 9 | 553 | 532 | 0.73% | 1,072 | 1 | City |
| Lake Lafayette | 10 | 310 | 279 | 1.97% | 484 | 1 | City |
| Lake Lafayette | 11 | 310 | 280 | 1.97% | 484 | 1 | City |
| Chilhowee | 12 | 294 | 287 | 0.34% | 814 | 0 | Town |
| Chilhowee | 13 | 294 | 287 | 0.34% | 814 | 0 | Town |
| Kingsville | 14 | 250 | 242 | 0.4% | 809 | 0 | City |
| Kingsville | 15 | 250 | 242 | 0.4% | 809 | 0 | City |
| Centerview | 16 | 198 | 190 | 0.51% | 1,010 | 0 | City |
| Centerview | 17 | 198 | 190 | 0.51% | 1,010 | 0 | City |
| Aullville | 18 | 79 | 77 | 0% | 297 | 0 | Village |
| Aullville | 19 | 79 | 77 | 0% | 297 | 0 | Village |
Warrensburg is the largest city in Johnson County, with a population of 20,159.
Aullville is the smallest city in Johnson County, with a population of 79.
There are 19 cities in Johnson County, Missouri.