17 cities
| City | Rank | 2025 Pop. ↓ | 2020 Pop. | Annual Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| DeForest | 1 | 12,620 | 10,819 | 2.94% | 1,328 | 10 | Village |
| Portage | 2 | 9,822 | 10,585 | -1.53% | 1,103 | 9 | City |
| Columbus | 3 | 5,403 | 5,531 | -0.48% | 1,190 | 5 | City |
| Prairie du Sac | 4 | 4,341 | 4,423 | -0.39% | 2,178 | 2 | Village |
| Lodi | 5 | 3,201 | 3,195 | 0.03% | 1,848 | 2 | City |
| Wisconsin Dells | 6 | 3,192 | 3,016 | 1.11% | 407 | 8 | City |
| Poynette | 7 | 2,892 | 2,600 | 2.05% | 1,126 | 3 | Village |
| Pardeeville | 8 | 2,304 | 2,072 | 2.04% | 1,197 | 2 | Village |
| Fall River | 9 | 1,852 | 1,854 | -0.05% | 981 | 2 | Village |
| Randolph | 10 | 1,753 | 1,797 | -0.51% | 1,413 | 1 | Village |
| West Baraboo | 11 | 1,575 | 1,628 | -0.69% | 1,249 | 1 | Village |
| Rio | 12 | 1,126 | 1,126 | 0% | 898 | 1 | Village |
| Arlington | 13 | 825 | 849 | -0.6% | 796 | 1 | Village |
| Cambria | 14 | 766 | 773 | -0.26% | 780 | 1 | Village |
| Wyocena | 15 | 725 | 760 | -0.96% | 506 | 1 | Village |
| Friesland | 16 | 312 | 316 | -0.32% | 309 | 1 | Village |
| Doylestown | 17 | 273 | 278 | -0.36% | 70 | 4 | Village |
DeForest is the largest city in Columbia County, with a population of 12,620.
Doylestown is the smallest city in Columbia County, with a population of 273.
There are 17 cities in Columbia County, Wisconsin.