90 cities
| City | Rank | 2025 Pop. ↓ | 2020 Pop. | Annual Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Washington | 1 | 3,527 | 3,532 | 0.09% | 61 | 58 | Township |
| Washington | 2 | 3,527 | 3,530 | 0.09% | 61 | 58 | Township |
| Washington | 3 | 2,974 | 2,926 | 0.61% | 91 | 33 | Township |
| Washington | 4 | 2,974 | 2,912 | 0.61% | 91 | 33 | Township |
| Washington | 5 | 1,076 | 1,068 | 0.09% | 1,107 | 1 | City |
| Washington | 6 | 1,076 | 1,069 | 0.09% | 1,107 | 1 | City |
| Hanover | 7 | 945 | 937 | 0.21% | 26 | 36 | Township |
| Hanover | 8 | 945 | 936 | 0.21% | 26 | 36 | Township |
| Hanover | 9 | 697 | 693 | 0.14% | 1,164 | 1 | City |
| Hanover | 10 | 697 | 692 | 0.14% | 1,164 | 1 | City |
| Linn | 11 | 518 | 514 | 0.19% | 14 | 36 | Township |
| Linn | 12 | 518 | 515 | 0.19% | 14 | 36 | Township |
| Clifton | 13 | 457 | 452 | 0.22% | 1,120 | 0 | City |
| Clifton | 14 | 457 | 452 | 0.22% | 1,120 | 0 | City |
| Washington | 15 | 448 | 471 | -1.1% | 10 | 45 | Township |
| Washington | 16 | 448 | 469 | -1.1% | 10 | 45 | Township |
| Greenleaf | 17 | 439 | 435 | 0.23% | 12 | 36 | Township |
| Greenleaf | 18 | 439 | 435 | 0.23% | 12 | 36 | Township |
| Linn | 19 | 389 | 386 | 0% | 1,147 | 0 | City |
| Linn | 20 | 389 | 387 | 0% | 1,147 | 0 | City |
| Washington | 21 | 384 | 398 | -0.26% | 11 | 36 | Township |
| Washington | 22 | 384 | 397 | -0.26% | 11 | 36 | Township |
| Clifton | 23 | 376 | 365 | 0.8% | 10 | 36 | Township |
| Clifton | 24 | 376 | 365 | 0.8% | 10 | 36 | Township |
| Greenleaf | 25 | 351 | 349 | 0% | 777 | 0 | City |
| Greenleaf | 26 | 351 | 349 | 0% | 777 | 0 | City |
| Clifton | 27 | 325 | 332 | 0% | 9 | 36 | Township |
| Clifton | 28 | 325 | 330 | 0% | 9 | 36 | Township |
| Washington | 29 | 315 | 307 | 0.64% | 9 | 35 | Township |
| Washington | 30 | 315 | 307 | 0.64% | 9 | 35 | Township |
| Sherman | 31 | 266 | 262 | 0.76% | 7 | 36 | Township |
| Sherman | 32 | 266 | 262 | 0.76% | 7 | 36 | Township |
| Barnes | 33 | 223 | 222 | -0.45% | 6 | 36 | Township |
| Barnes | 34 | 223 | 222 | -0.45% | 6 | 36 | Township |
| Mill Creek | 35 | 183 | 181 | 0.55% | 5 | 36 | Township |
| Mill Creek | 36 | 183 | 181 | 0.55% | 5 | 36 | Township |
| Farmington | 37 | 175 | 174 | 0.57% | 5 | 36 | Township |
| Farmington | 38 | 175 | 174 | 0.57% | 5 | 36 | Township |
| Washington | 39 | 171 | 171 | 0% | 5 | 35 | Township |
| Washington | 40 | 171 | 171 | 0% | 5 | 35 | Township |
| Haddam | 41 | 165 | 163 | 0.61% | 5 | 36 | Township |
| Haddam | 42 | 165 | 163 | 0.61% | 5 | 36 | Township |
| Barnes | 43 | 163 | 163 | 0% | 959 | 0 | City |
| Barnes | 44 | 163 | 163 | 0% | 959 | 0 | City |
| Washington | 45 | 147 | 148 | 0% | 4 | 36 | Township |
| Washington | 46 | 147 | 148 | 0% | 4 | 36 | Township |
| Palmer | 47 | 126 | 124 | 0% | 408 | 0 | City |
| Palmer | 48 | 126 | 124 | 0% | 408 | 0 | City |
| Morrowville | 49 | 116 | 116 | 0% | 811 | 0 | City |
| Morrowville | 50 | 116 | 116 | 0% | 811 | 0 | City |
| Strawberry | 51 | 111 | 108 | 0.91% | 3 | 36 | Township |
| Strawberry | 52 | 111 | 108 | 0.91% | 3 | 36 | Township |
| Haddam | 53 | 108 | 108 | 0% | 315 | 0 | City |
| Haddam | 54 | 108 | 108 | 0% | 315 | 0 | City |
| Sheridan | 55 | 104 | 103 | 0% | 3 | 36 | Township |
| Sheridan | 56 | 104 | 103 | 0% | 3 | 36 | Township |
| Little Blue | 57 | 76 | 75 | 0% | 2 | 36 | Township |
| Little Blue | 58 | 76 | 75 | 0% | 2 | 36 | Township |
| Washington | 59 | 75 | 71 | 1.35% | 1 | 57 | Township |
| Washington | 60 | 75 | 71 | 1.35% | 1 | 57 | Township |
| Brantford | 61 | 74 | 73 | 0% | 2 | 36 | Township |
| Brantford | 62 | 74 | 73 | 0% | 2 | 36 | Township |
| Washington | 63 | 66 | 68 | -1.49% | 1 | 47 | Township |
| Washington | 64 | 66 | 68 | -1.49% | 1 | 47 | Township |
| Charleston | 65 | 65 | 64 | 0% | 2 | 35 | Township |
| Charleston | 66 | 65 | 64 | 0% | 2 | 35 | Township |
| Washington | 67 | 63 | 64 | 0% | 1 | 54 | Township |
| Washington | 68 | 63 | 64 | 0% | 1 | 54 | Township |
| Coleman | 69 | 62 | 61 | 0% | 2 | 36 | Township |
| Coleman | 70 | 62 | 61 | 0% | 2 | 36 | Township |
| Union | 71 | 61 | 61 | 0% | 2 | 36 | Township |
| Union | 72 | 61 | 61 | 0% | 2 | 36 | Township |
| Washington | 73 | 59 | 59 | 0% | 2 | 36 | Township |
| Washington | 74 | 59 | 59 | 0% | 2 | 36 | Township |
| Washington | 75 | 57 | 57 | 0% | 2 | 36 | Township |
| Washington | 76 | 57 | 57 | 0% | 2 | 36 | Township |
| Kimeo | 77 | 51 | 49 | 2% | 1 | 36 | Township |
| Kimeo | 78 | 51 | 49 | 2% | 1 | 36 | Township |
| Hanover | 79 | 49 | 49 | 0% | 1 | 36 | Township |
| Hanover | 80 | 49 | 49 | 0% | 1 | 36 | Township |
| Lowe | 81 | 48 | 46 | 2.13% | 1 | 35 | Township |
| Lowe | 82 | 48 | 46 | 2.13% | 1 | 35 | Township |
| Grant | 83 | 47 | 45 | 2.17% | 1 | 36 | Township |
| Grant | 84 | 47 | 45 | 2.17% | 1 | 36 | Township |
| Washington | 85 | 45 | 45 | 0% | 1 | 36 | Township |
| Washington | 86 | 45 | 45 | 0% | 1 | 36 | Township |
| Mahaska | 87 | 44 | 44 | 0% | 197 | 0 | City |
| Mahaska | 88 | 44 | 44 | 0% | 197 | 0 | City |
| Hollenberg | 89 | 12 | 12 | 0% | 164 | 0 | City |
| Hollenberg | 90 | 12 | 12 | 0% | 164 | 0 | City |
Washington is the largest city in Washington County, with a population of 3,527.
Hollenberg is the smallest city in Washington County, with a population of 12.
There are 90 cities in Washington County, Kansas.