16 cities
| City | Rank | 2025 Pop. ↓ | 2020 Pop. | Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Leavenworth | 1 | 36,842 | 37,322 | -0.26% | 1,513 | 24.36 | City |
| Fairmount township | 2 | 12,648 | 11,319 | 1.7% | 322 | 39.23 | Township |
| Lansing | 3 | 11,211 | 11,236 | -0.04% | 912 | 12.30 | City |
| Basehor | 4 | 8,241 | 6,935 | 3.27% | 1,154 | 7.14 | City |
| Tonganoxie township | 5 | 6,679 | 5,970 | 2.61% | 126 | 53.09 | Township |
| Tonganoxie | 6 | 6,442 | 5,592 | 2.71% | 1,587 | 4.06 | City |
| Stranger township | 7 | 5,661 | 5,104 | 2.37% | 116 | 48.89 | Township |
| Sherman township | 8 | 2,913 | 2,795 | 0.76% | 70 | 41.43 | Township |
| High Prairie township | 9 | 2,131 | 2,034 | 0.95% | 45 | 47.37 | Township |
| Kickapoo township | 10 | 1,861 | 1,782 | 0.81% | 42 | 44.12 | Township |
| Reno township | 11 | 1,479 | 1,418 | 0.82% | 35 | 42.69 | Township |
| Delaware township | 12 | 1,114 | 1,069 | 0.81% | 56 | 19.87 | Township |
| Easton township | 13 | 1,096 | 1,059 | 0.74% | 26 | 42.30 | Township |
| Alexandria township | 14 | 884 | 851 | 0.68% | 19 | 47.54 | Township |
| Linwood | 15 | 432 | 414 | 0.93% | 732 | 0.59 | City |
| Easton | 16 | 211 | 211 | 0% | 1,249 | 0.17 | City |
Leavenworth is the largest city in Leavenworth County, with a population of 36,842.
Easton is the smallest city in Leavenworth County.
There are 16 cities in Leavenworth County, Kansas.