11 cities
| City | Rank | 2025 Pop. ↓ | 2020 Pop. | Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Independence | 1 | 6,254 | 6,089 | 0.53% | 1,037 | 6.03 | City |
| Jesup | 2 | 2,553 | 2,513 | 0.31% | 1,387 | 1.84 | City |
| Fairbank | 3 | 1,141 | 1,108 | 0.62% | 1,552 | 0.73 | City |
| Winthrop | 4 | 814 | 823 | -0.24% | 1,029 | 0.79 | City |
| Hazleton | 5 | 709 | 711 | 0% | 887 | 0.80 | City |
| Quasqueton | 6 | 601 | 576 | 0.84% | 532 | 1.13 | City |
| Lamont | 7 | 432 | 432 | 0% | 738 | 0.58 | City |
| Brandon | 8 | 330 | 337 | -0.3% | 1,019 | 0.32 | City |
| Rowley | 9 | 264 | 269 | -0.38% | 680 | 0.39 | City |
| Aurora | 10 | 166 | 166 | 0% | 314 | 0.53 | City |
| Stanley | 11 | 85 | 85 | 0% | 419 | 0.20 | City |
Independence is the largest city in Buchanan County, with a population of 6,254.
Stanley is the smallest city in Buchanan County.
There are 11 cities in Buchanan County, Iowa.