17 cities
| City | Rank | 2025 Pop. ↓ | 2020 Pop. | Annual Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Charles City | 1 | 7,006 | 7,399 | -1.06% | 1,144 | 6 | City |
| Charles City | 2 | 7,006 | 7,381 | -1.06% | 1,144 | 6 | City |
| Nora Springs | 3 | 1,321 | 1,367 | -0.68% | 596 | 2 | City |
| Nora Springs | 4 | 1,321 | 1,364 | -0.68% | 596 | 2 | City |
| Rockford | 5 | 712 | 761 | -1.39% | 1,143 | 1 | City |
| Rockford | 6 | 712 | 760 | -1.39% | 1,143 | 1 | City |
| Rudd | 7 | 335 | 356 | -1.18% | 308 | 1 | City |
| Rudd | 8 | 335 | 355 | -1.18% | 308 | 1 | City |
| Floyd | 9 | 294 | 310 | -1.01% | 533 | 1 | City |
| Floyd | 10 | 294 | 309 | -1.01% | 533 | 1 | City |
| Marble Rock | 11 | 255 | 269 | -1.16% | 306 | 1 | City |
| Marble Rock | 12 | 255 | 269 | -1.16% | 306 | 1 | City |
| Mitchell | 13 | 117 | 122 | -0.85% | 207 | 1 | City |
| Mitchell | 14 | 117 | 122 | -0.85% | 207 | 1 | City |
| New Haven | 15 | 72 | 103 | 5.88% | 37 | 2 | CDP |
| Colwell | 16 | 51 | 54 | -1.92% | 309 | 0 | City |
| Colwell | 17 | 51 | 54 | -1.92% | 309 | 0 | City |
Charles City is the largest city in Floyd County, with a population of 7,006.
Colwell is the smallest city in Floyd County, with a population of 51.
There are 17 cities in Floyd County, Iowa.