15 cities
| City | Rank | 2025 Pop. ↓ | 2020 Pop. | Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Salem | 1 | 6,365 | 6,545 | -0.56% | 1,507 | 4.22 | City |
| Salem township | 2 | 4,102 | 3,971 | 0.69% | 117 | 35.06 | Township |
| Polk township | 3 | 2,745 | 2,694 | 0.51% | 77 | 35.84 | Township |
| Pierce township | 4 | 2,506 | 2,492 | 0.16% | 70 | 35.62 | Township |
| Salem township | 5 | 2,187 | 2,140 | 0.46% | 64 | 33.92 | Township |
| Jackson township | 6 | 2,047 | 2,048 | 0.1% | 81 | 25.39 | Township |
| Posey township | 7 | 1,822 | 1,825 | 0% | 54 | 33.55 | Township |
| Salem township | 8 | 1,252 | 1,298 | -0.87% | 35 | 35.79 | Township |
| Howard township | 9 | 1,220 | 1,218 | 0% | 34 | 35.82 | Township |
| Gibson township | 10 | 1,130 | 1,120 | 0.27% | 22 | 50.97 | Township |
| Brown township | 11 | 1,105 | 1,079 | 0.64% | 36 | 30.73 | Township |
| Jefferson township | 12 | 879 | 851 | 0.8% | 18 | 48.10 | Township |
| Campbellsburg | 13 | 538 | 533 | 0.19% | 542 | 0.99 | Town |
| Little York | 14 | 187 | 189 | 0% | 191 | 0.98 | Town |
| Fredericksburg | 15 | 46 | 41 | 6.98% | 43 | 1.07 | CDP |
Salem is the largest city in Washington County, with a population of 6,365.
Fredericksburg is the smallest city in Washington County.
There are 15 cities in Washington County, Indiana.