9 cities
| City | Rank | 2026 Pop. ↓ | 2020 Pop. | Annual Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Warrensburg | 1 | 20,321 | 19,351 | 0.8% | 2,160 | 9 | City |
| Knob Noster | 2 | 3,018 | 2,760 | 1.45% | 1,048 | 3 | City |
| Holden | 3 | 2,359 | 2,209 | 1.07% | 978 | 2 | City |
| Leeton | 4 | 557 | 532 | 0.72% | 1,079 | 1 | City |
| Lake Lafayette | 5 | 316 | 280 | 1.94% | 493 | 1 | City |
| Chilhowee | 6 | 296 | 287 | 0.68% | 820 | 0 | Town |
| Kingsville | 7 | 252 | 242 | 0.8% | 816 | 0 | City |
| Centerview | 8 | 200 | 190 | 1.01% | 1,020 | 0 | City |
| Aullville | 9 | 80 | 77 | 1.27% | 301 | 0 | Village |
Warrensburg is the largest city in Johnson County, with a population of 20,321.
Aullville is the smallest city in Johnson County, with a population of 80.
There are 9 cities in Johnson County, Missouri.