9 cities
| City | Rank | 2026 Pop. ↓ | 2020 Pop. | Annual Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| South Kingstown | 1 | 32,148 | 31,925 | 0.08% | 570 | 56 | Town |
| North Kingstown | 2 | 28,132 | 27,708 | 0.35% | 652 | 43 | Town |
| Westerly | 3 | 23,314 | 23,321 | 0.06% | 791 | 29 | Town |
| Narragansett | 4 | 14,349 | 14,504 | -0.2% | 1,035 | 14 | Town |
| Hopkinton | 5 | 8,455 | 8,399 | 0.14% | 197 | 43 | Town |
| Richmond | 6 | 8,136 | 8,054 | -0.04% | 202 | 40 | Town |
| Charlestown | 7 | 8,052 | 7,992 | 0% | 220 | 37 | Town |
| Exeter | 8 | 6,516 | 6,460 | -0.4% | 113 | 57 | Town |
| New Shoreham | 9 | 1,419 | 1,406 | 0.21% | 156 | 9 | Town |
South Kingstown is the largest city in Washington County, with a population of 32,148.
New Shoreham is the smallest city in Washington County, with a population of 1,419.
There are 9 cities in Washington County, Rhode Island.