| City | Rank | 2026 Pop. ↓ | 2020 Pop. | Annual Change | Density (/mi²) | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Maquoketa | 1 | 6,010 | 6,122 | -0.28% | 1,331 | 5 | City |
| Bellevue | 2 | 2,308 | 2,355 | -0.39% | 1,533 | 2 | City |
| Preston | 3 | 933 | 946 | -0.21% | 1,084 | 1 | City |
| Sabula | 4 | 495 | 500 | -0.2% | 1,002 | 0 | City |
| Miles | 5 | 395 | 409 | -0.75% | 313 | 1 | City |
| Andrew | 6 | 368 | 375 | -0.27% | 1,484 | 0 | City |
| La Motte | 7 | 232 | 238 | -0.85% | 512 | 0 | City |
| Springbrook | 8 | 140 | 140 | 0% | 231 | 1 | City |
| Monmouth | 9 | 128 | 129 | 0% | 225 | 1 | City |
| St. Donatus | 10 | 120 | 123 | -0.83% | 321 | 0 | City |
| Baldwin | 11 | 97 | 100 | -1.02% | 255 | 0 | City |
| Spragueville | 12 | 91 | 91 | 0% | 122 | 1 | City |
Maquoketa is the largest city in Jackson County, with a population of 6,010.
Spragueville is the smallest city in Jackson County, with a population of 91.
There are 12 cities in Jackson County, Iowa.