38 cities
| City | Rank | 2026 Pop. ↓ | 2020 Pop. | Annual Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Bruno | 1 | 21,147 | 16,881 | 5.7% | 604 | 35 | Township |
| Andover | 2 | 18,016 | 14,967 | 2.9% | 1,636 | 11 | City |
| El Dorado | 3 | 12,655 | 12,771 | -0.15% | 1,272 | 10 | City |
| Augusta | 4 | 9,034 | 9,241 | -0.37% | 2,130 | 4 | City |
| Pleasant | 5 | 5,354 | 5,348 | -0.74% | 149 | 36 | Township |
| Rose Hill | 6 | 4,341 | 4,188 | 0.6% | 1,924 | 2 | City |
| Richland | 7 | 2,560 | 2,583 | -1.12% | 71 | 36 | Township |
| Prospect | 8 | 2,556 | 2,551 | -0.31% | 32 | 79 | Township |
| Towanda | 9 | 2,503 | 2,601 | -1.34% | 70 | 36 | Township |
| Benton | 10 | 2,276 | 2,378 | -1.56% | 63 | 36 | Township |
| Douglass | 11 | 1,902 | 2,007 | -1.71% | 53 | 36 | Township |
| Douglass | 12 | 1,496 | 1,549 | -0.6% | 1,409 | 1 | City |
| Spring | 13 | 1,419 | 1,479 | -1.53% | 39 | 36 | Township |
| Towanda | 14 | 1,414 | 1,443 | -0.35% | 1,547 | 1 | City |
| Augusta | 15 | 1,194 | 1,227 | -1.24% | 37 | 32 | Township |
| Benton | 16 | 934 | 933 | 0.43% | 16 | 60 | Township |
| Benton | 17 | 923 | 944 | -0.32% | 601 | 2 | City |
| Little Walnut | 18 | 905 | 934 | -1.42% | 25 | 36 | Township |
| Whitewater | 19 | 648 | 660 | -0.31% | 1,577 | 0 | City |
| Leon | 20 | 645 | 656 | -0.31% | 892 | 1 | City |
| El Dorado | 21 | 628 | 648 | -1.26% | 12 | 51 | Township |
| Plum Grove | 22 | 565 | 590 | -1.4% | 16 | 36 | Township |
| Rosalia | 23 | 535 | 557 | -1.65% | 9 | 63 | Township |
| Bloomington | 24 | 488 | 491 | -1.21% | 14 | 36 | Township |
| Fairmount | 25 | 457 | 481 | -1.72% | 13 | 36 | Township |
| Potwin | 26 | 409 | 421 | -0.49% | 1,740 | 0 | City |
| Rock Creek | 27 | 286 | 297 | -1.72% | 8 | 36 | Township |
| Chelsea | 28 | 272 | 273 | -0.73% | 3 | 101 | Township |
| Elbing | 29 | 217 | 225 | -0.46% | 1,262 | 0 | City |
| Clifford | 30 | 204 | 212 | -1.92% | 5 | 42 | Township |
| Glencoe | 31 | 167 | 175 | -1.76% | 3 | 62 | Township |
| Union | 32 | 134 | 142 | -2.19% | 2 | 62 | Township |
| Cassoday | 33 | 105 | 107 | 0% | 309 | 0 | City |
| Latham | 34 | 97 | 99 | 0% | 447 | 0 | City |
| Hickory | 35 | 81 | 85 | -1.22% | 1 | 62 | Township |
| Clay | 36 | 68 | 62 | 1.49% | 2 | 36 | Township |
| Benton | 37 | 27 | 30 | -3.57% | 1 | 36 | Township |
| Towanda | 38 | 24 | 25 | 0% | 1 | 36 | Township |
Bruno is the largest city in Butler County, with a population of 21,147.
Towanda is the smallest city in Butler County, with a population of 24.
There are 38 cities in Butler County, Kansas.