9 cities
| City | Rank | 2025 Pop. ↓ | 2020 Pop. | Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| South Kingstown | 1 | 31,935 | 31,930 | -0.14% | 567 | 56.37 | Town |
| North Kingstown | 2 | 27,735 | 27,702 | -0.07% | 642 | 43.17 | Town |
| Westerly | 3 | 23,085 | 23,322 | -0.3% | 783 | 29.47 | Town |
| Narragansett | 4 | 14,239 | 14,511 | -0.59% | 1,027 | 13.87 | Town |
| Hopkinton | 5 | 8,378 | 8,398 | -0.13% | 195 | 43.01 | Town |
| Richmond | 6 | 8,113 | 8,056 | -0.12% | 201 | 40.32 | Town |
| Charlestown | 7 | 8,030 | 7,992 | -0.04% | 220 | 36.54 | Town |
| Exeter | 8 | 6,523 | 6,462 | -0.44% | 114 | 57.45 | Town |
| New Shoreham | 9 | 1,396 | 1,403 | -0.29% | 154 | 9.08 | Town |
South Kingstown is the largest city in Washington County, with a population of 31,935.
New Shoreham is the smallest city in Washington County.
There are 9 cities in Washington County, Rhode Island.