11 cities
| City | Rank | 2025 Pop. ↓ | 2020 Pop. | Annual Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Independence | 1 | 6,311 | 6,084 | 0.72% | 1,047 | 6 | City |
| Jesup | 2 | 2,547 | 2,514 | 0.24% | 1,383 | 2 | City |
| Fairbank | 3 | 1,138 | 1,110 | 0.44% | 1,548 | 1 | City |
| Winthrop | 4 | 811 | 825 | -0.37% | 1,025 | 1 | City |
| Hazleton | 5 | 711 | 711 | 0% | 890 | 1 | City |
| Quasqueton | 6 | 589 | 576 | 0.34% | 521 | 1 | City |
| Lamont | 7 | 428 | 432 | -0.23% | 732 | 1 | City |
| Brandon | 8 | 329 | 336 | -0.6% | 1,015 | 0 | City |
| Rowley | 9 | 262 | 269 | -0.76% | 675 | 0 | City |
| Aurora | 10 | 164 | 166 | -0.61% | 310 | 1 | City |
| Stanley | 11 | 86 | 86 | 0% | 424 | 0 | City |
Independence is the largest city in Buchanan County, with a population of 6,311.
Stanley is the smallest city in Buchanan County, with a population of 86.
There are 11 cities in Buchanan County, Iowa.