36 cities
| City | Rank | 2025 Pop. ↓ | 2020 Pop. | Annual Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| DeForest | 1 | 12,620 | 10,805 | 2.94% | 1,453 | 9 | Village |
| DeForest | 2 | 12,620 | 10,819 | 2.94% | 1,453 | 9 | Village |
| Portage | 3 | 9,822 | 10,590 | -1.53% | 1,103 | 9 | City |
| Portage | 4 | 9,822 | 10,585 | -1.53% | 1,103 | 9 | City |
| Columbus | 5 | 5,403 | 5,534 | -0.48% | 1,190 | 5 | City |
| Columbus | 6 | 5,403 | 5,531 | -0.48% | 1,190 | 5 | City |
| Lake Wisconsin | 7 | 5,060 | 4,573 | 1.16% | 378 | 13 | CDP |
| Prairie Sac | 8 | 4,341 | 4,425 | -0.39% | 2,248 | 2 | Village |
| Prairie Sac | 9 | 4,341 | 4,423 | -0.39% | 2,248 | 2 | Village |
| Lodi | 10 | 3,201 | 3,191 | 0.03% | 1,848 | 2 | City |
| Lodi | 11 | 3,201 | 3,195 | 0.03% | 1,848 | 2 | City |
| Wisconsin Dells | 12 | 3,192 | 2,948 | 1.11% | 407 | 8 | City |
| Wisconsin Dells | 13 | 3,192 | 3,016 | 1.11% | 407 | 8 | City |
| Poynette | 14 | 2,892 | 2,600 | 2.05% | 1,126 | 3 | Village |
| Poynette | 15 | 2,892 | 2,600 | 2.05% | 1,126 | 3 | Village |
| Pardeeville | 16 | 2,304 | 2,074 | 2.04% | 1,197 | 2 | Village |
| Pardeeville | 17 | 2,304 | 2,072 | 2.04% | 1,197 | 2 | Village |
| Fall River | 18 | 1,852 | 1,853 | -0.05% | 981 | 2 | Village |
| Fall River | 19 | 1,852 | 1,854 | -0.05% | 981 | 2 | Village |
| Randolph | 20 | 1,753 | 1,797 | -0.51% | 1,413 | 1 | Village |
| Randolph | 21 | 1,753 | 1,797 | -0.51% | 1,413 | 1 | Village |
| West Baraboo | 22 | 1,575 | 1,629 | -0.69% | 1,249 | 1 | Village |
| West Baraboo | 23 | 1,575 | 1,628 | -0.69% | 1,249 | 1 | Village |
| Rio | 24 | 1,126 | 1,123 | 0% | 898 | 1 | Village |
| Rio | 25 | 1,126 | 1,126 | 0% | 898 | 1 | Village |
| Arlington | 26 | 825 | 847 | -0.6% | 796 | 1 | Village |
| Arlington | 27 | 825 | 849 | -0.6% | 796 | 1 | Village |
| Cambria | 28 | 766 | 772 | -0.26% | 780 | 1 | Village |
| Cambria | 29 | 766 | 773 | -0.26% | 780 | 1 | Village |
| Wyocena | 30 | 725 | 759 | -0.96% | 506 | 1 | Village |
| Wyocena | 31 | 725 | 760 | -0.96% | 506 | 1 | Village |
| Friesland | 32 | 312 | 316 | -0.32% | 309 | 1 | Village |
| Friesland | 33 | 312 | 316 | -0.32% | 309 | 1 | Village |
| Doylestown | 34 | 273 | 278 | -0.36% | 70 | 4 | Village |
| Doylestown | 35 | 273 | 278 | -0.36% | 70 | 4 | Village |
| Dekorra | 36 | 136 | 105 | 7.09% | 112 | 1 | CDP |
DeForest is the largest city in Columbia County, with a population of 12,620.
Dekorra is the smallest city in Columbia County, with a population of 136.
There are 36 cities in Columbia County, Wisconsin.