| City | Rank | 2026 Pop. ↓ | 2020 Pop. | Annual Change | Density (/mi²) | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| South Kingstown | 1 | 32,009 | 31,928 | 0% | 568 | 56 | Town |
| North Kingstown | 2 | 27,925 | 27,702 | 0.14% | 647 | 43 | Town |
| Westerly | 3 | 23,061 | 23,327 | -0.34% | 783 | 29 | Town |
| Narragansett | 4 | 14,214 | 14,511 | -0.54% | 1,025 | 14 | Town |
| Hopkinton | 5 | 8,392 | 8,392 | -0.01% | 195 | 43 | Town |
| Richmond | 6 | 8,133 | 8,053 | 0.06% | 202 | 40 | Town |
| Charlestown | 7 | 7,972 | 7,995 | -0.37% | 218 | 37 | Town |
| Exeter | 8 | 6,516 | 6,463 | -0.37% | 113 | 57 | Town |
| New Shoreham | 9 | 1,410 | 1,404 | 0.14% | 155 | 9 | Town |
South Kingstown is the largest city in Washington County, with a population of 32,009.
New Shoreham is the smallest city in Washington County, with a population of 1,410.
There are 9 cities in Washington County, Rhode Island.