| City | Rank | 2026 Pop. ↓ | 2020 Pop. | Annual Change | Density (/mi²) | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Andover | 1 | 17,878 | 14,975 | 2.92% | 1,624 | 11 | City |
| El Dorado | 2 | 12,677 | 12,766 | -0.15% | 1,274 | 10 | City |
| Augusta | 3 | 9,037 | 9,237 | -0.4% | 2,130 | 4 | City |
| Rose Hill | 4 | 4,346 | 4,186 | 0.6% | 1,926 | 2 | City |
| Douglass | 5 | 1,497 | 1,548 | -0.6% | 1,410 | 1 | City |
| Towanda | 6 | 1,421 | 1,443 | -0.35% | 1,555 | 1 | City |
| Benton | 7 | 936 | 954 | -0.32% | 609 | 2 | City |
| Leon | 8 | 650 | 656 | -0.31% | 899 | 1 | City |
| Whitewater | 9 | 648 | 660 | -0.31% | 1,577 | 0 | City |
| Potwin | 10 | 408 | 423 | -0.73% | 1,736 | 0 | City |
| Elbing | 11 | 221 | 226 | -0.9% | 1,285 | 0 | City |
| Cassoday | 12 | 107 | 108 | 0% | 315 | 0 | City |
| Latham | 13 | 98 | 100 | -1.01% | 452 | 0 | City |
Andover is the largest city in Butler County, with a population of 17,878.
Latham is the smallest city in Butler County, with a population of 98.
There are 13 cities in Butler County, Kansas.