29 cities
| City | Rank | 2025 Pop. ↓ | 2020 Pop. | Annual Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Woodbury | 1 | 81,875 | 75,480 | 1.59% | 2,346 | 35 | City |
| Cottage Grove | 2 | 43,702 | 38,990 | 2.2% | 1,299 | 34 | City |
| Oakdale | 3 | 30,983 | 28,270 | 1.78% | 2,827 | 11 | City |
| Forest Lake | 4 | 20,699 | 20,702 | 0% | 678 | 31 | City |
| Stillwater | 5 | 19,381 | 19,404 | -0.03% | 2,409 | 8 | City |
| Hugo | 6 | 17,004 | 15,808 | 1.43% | 508 | 33 | City |
| Lake Elmo | 7 | 14,863 | 11,351 | 4.96% | 673 | 22 | City |
| Mahtomedi | 8 | 8,213 | 8,143 | 0.17% | 2,368 | 3 | City |
| Newport | 9 | 5,783 | 3,940 | 6.8% | 1,598 | 4 | City |
| St. Paul Park | 10 | 5,340 | 5,545 | -0.76% | 1,781 | 3 | City |
| Oak Park Heights | 11 | 4,631 | 4,843 | -0.92% | 1,583 | 3 | City |
| Scandia | 12 | 3,942 | 3,987 | -0.23% | 113 | 35 | City |
| West Lakeland | 13 | 3,925 | 3,979 | -0.05% | 318 | 12 | Township |
| Bayport | 14 | 3,723 | 4,030 | -1.64% | 2,148 | 2 | City |
| Afton | 15 | 2,948 | 2,953 | -0.03% | 117 | 25 | City |
| May | 16 | 2,626 | 2,670 | 0.19% | 77 | 34 | Township |
| Baytown | 17 | 2,223 | 2,099 | 1.65% | 275 | 8 | Township |
| Denmark | 18 | 1,891 | 1,812 | 0.11% | 66 | 28 | Township |
| Stillwater | 19 | 1,831 | 1,867 | 0.27% | 125 | 15 | Township |
| Lakeland | 20 | 1,651 | 1,713 | -0.78% | 796 | 2 | City |
| Lake St. Croix Beach | 21 | 996 | 1,041 | -0.9% | 1,772 | 1 | City |
| Landfall | 22 | 842 | 845 | -0.12% | 12,758 | 0 | City |
| Marine St. Croix | 23 | 656 | 663 | -0.3% | 168 | 4 | City |
| Willernie | 24 | 510 | 519 | -0.39% | 4,080 | 0 | City |
| Pine Springs | 25 | 382 | 391 | -0.52% | 496 | 1 | City |
| St. Marys Point | 26 | 339 | 351 | -0.88% | 878 | 0 | City |
| Lakeland Shores | 27 | 327 | 341 | -0.91% | 1,035 | 0 | City |
| Grey Cloud Island | 28 | 304 | 281 | 0% | 144 | 2 | Township |
| Scandia | 29 | 68 | 66 | 3.03% | 2 | 36 | Township |
Woodbury is the largest city in Washington County, with a population of 81,875.
Scandia is the smallest city in Washington County, with a population of 68.
There are 29 cities in Washington County, Minnesota.