15 cities
| City | Rank | 2025 Pop. ↓ | 2020 Pop. | Annual Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Salem | 1 | 6,439 | 6,556 | -0.37% | 1,525 | 4 | City |
| Salem | 2 | 4,086 | 3,971 | 0.42% | 117 | 35 | Township |
| Polk | 3 | 2,737 | 2,683 | 0.66% | 76 | 36 | Township |
| Pierce | 4 | 2,534 | 2,493 | 0.68% | 71 | 36 | Township |
| Salem | 5 | 2,162 | 2,138 | 0% | 64 | 34 | Township |
| Jackson | 6 | 2,070 | 2,048 | 0.58% | 82 | 25 | Township |
| Posey | 7 | 1,855 | 1,829 | 0.54% | 55 | 34 | Township |
| Salem | 8 | 1,267 | 1,299 | -0.47% | 35 | 36 | Township |
| Howard | 9 | 1,228 | 1,219 | 0.49% | 34 | 36 | Township |
| Gibson | 10 | 1,145 | 1,121 | 0.7% | 22 | 51 | Township |
| Brown | 11 | 1,104 | 1,079 | 0.73% | 36 | 31 | Township |
| Jefferson | 12 | 871 | 850 | 0.81% | 18 | 48 | Township |
| Campbellsburg | 13 | 540 | 533 | 0.19% | 544 | 1 | Town |
| Little York | 14 | 191 | 189 | 0% | 195 | 1 | Town |
| Fredericksburg | 15 | 46 | 41 | 6.98% | 43 | 1 | CDP |
Salem is the largest city in Washington County, with a population of 6,439.
Fredericksburg is the smallest city in Washington County, with a population of 46.
There are 15 cities in Washington County, Indiana.