29 cities
| City | Rank | 2026 Pop. ↓ | 2020 Pop. | Annual Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Woodbury | 1 | 83,154 | 75,480 | 1.56% | 2,383 | 35 | City |
| Cottage Grove | 2 | 44,645 | 38,990 | 2.16% | 1,327 | 34 | City |
| Oakdale | 3 | 31,526 | 28,270 | 1.75% | 2,876 | 11 | City |
| Forest Lake | 4 | 20,699 | 20,702 | 0% | 678 | 31 | City |
| Stillwater | 5 | 19,377 | 19,404 | -0.02% | 2,408 | 8 | City |
| Hugo | 6 | 17,243 | 15,808 | 1.41% | 515 | 33 | City |
| Lake Elmo | 7 | 15,566 | 11,351 | 4.73% | 705 | 22 | City |
| Mahtomedi | 8 | 8,227 | 8,143 | 0.17% | 2,372 | 3 | City |
| Newport | 9 | 6,152 | 3,940 | 6.38% | 1,700 | 4 | City |
| St. Paul Park | 10 | 5,299 | 5,545 | -0.77% | 1,768 | 3 | City |
| Oak Park Heights | 11 | 4,589 | 4,843 | -0.91% | 1,568 | 3 | City |
| Scandia | 12 | 3,933 | 3,987 | -0.23% | 113 | 35 | City |
| West Lakeland | 13 | 3,923 | 3,979 | -0.05% | 318 | 12 | Township |
| Bayport | 14 | 3,662 | 4,030 | -1.64% | 2,113 | 2 | City |
| Afton | 15 | 2,947 | 2,953 | -0.03% | 117 | 25 | City |
| May | 16 | 2,631 | 2,670 | 0.19% | 77 | 34 | Township |
| Baytown | 17 | 2,259 | 2,099 | 1.62% | 279 | 8 | Township |
| Denmark | 18 | 1,893 | 1,812 | 0.11% | 67 | 28 | Township |
| Stillwater | 19 | 1,836 | 1,867 | 0.27% | 125 | 15 | Township |
| Lakeland | 20 | 1,639 | 1,713 | -0.73% | 790 | 2 | City |
| Lake St. Croix Beach | 21 | 987 | 1,041 | -0.9% | 1,756 | 1 | City |
| Landfall | 22 | 842 | 845 | 0% | 12,758 | 0 | City |
| Marine on St. Croix | 23 | 655 | 663 | -0.15% | 168 | 4 | City |
| Willernie | 24 | 508 | 519 | -0.39% | 4,064 | 0 | City |
| Pine Springs | 25 | 380 | 391 | -0.52% | 494 | 1 | City |
| St. Marys Point | 26 | 337 | 351 | -0.59% | 873 | 0 | City |
| Lakeland Shores | 27 | 324 | 341 | -0.92% | 1,025 | 0 | City |
| Grey Cloud Island | 28 | 304 | 281 | 0% | 144 | 2 | Township |
| Scandia | 29 | 70 | 66 | 2.94% | 2 | 36 | Township |
Woodbury is the largest city in Washington County, with a population of 83,154.
Scandia is the smallest city in Washington County, with a population of 70.
There are 29 cities in Washington County, Minnesota.