| City | Rank | 2026 Pop. ↓ | 2020 Pop. | Annual Change | Density (/mi²) | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Wallkill | 1 | 31,147 | 30,554 | -0.85% | 503 | 62 | Town |
| Kingston | 2 | 23,875 | 23,959 | -0.28% | 3,191 | 7 | City |
| Milton | 3 | 19,630 | 18,812 | 0.43% | 550 | 36 | Town |
| Saugerties | 4 | 19,355 | 19,022 | -0.2% | 300 | 65 | Town |
| New Paltz | 5 | 15,589 | 14,398 | -0.3% | 460 | 34 | Town |
| Shawangunk | 6 | 13,734 | 13,403 | 0.92% | 245 | 56 | Town |
| Ulster | 7 | 12,623 | 12,639 | -0.18% | 471 | 27 | Town |
| Wawarsing | 8 | 12,368 | 12,588 | -0.64% | 95 | 131 | Town |
| Lloyd | 9 | 11,145 | 11,145 | 0.02% | 356 | 31 | Town |
| Plattekill | 10 | 10,322 | 10,382 | -0.14% | 294 | 35 | Town |
| Esopus | 11 | 9,537 | 9,552 | -0.07% | 256 | 37 | Town |
| Marlborough | 12 | 9,134 | 8,708 | 0.71% | 373 | 24 | Town |
| New Paltz | 13 | 9,025 | 7,359 | 3.87% | 5,122 | 2 | Village |
| Woodstock | 14 | 6,211 | 6,284 | -0.06% | 92 | 67 | Town |
| Hurley | 15 | 6,124 | 6,180 | -0.15% | 205 | 30 | Town |
| Marbletown | 16 | 5,780 | 5,657 | 0.36% | 106 | 54 | Town |
| Rosendale | 17 | 5,671 | 5,790 | -0.32% | 284 | 20 | Town |
| Gardiner | 18 | 5,617 | 5,611 | -0.07% | 129 | 43 | Town |
| Olive | 19 | 4,262 | 4,224 | -0.02% | 73 | 58 | Town |
| Ellenville | 20 | 4,188 | 4,271 | -0.31% | 482 | 9 | Village |
| Saugerties | 21 | 3,845 | 3,903 | -0.21% | 2,155 | 2 | Village |
| Shandaken | 22 | 2,803 | 2,855 | -0.36% | 23 | 120 | Town |
| Highland | 23 | 2,193 | 2,192 | -0.95% | 44 | 50 | Town |
| Kingston | 24 | 900 | 919 | -0.44% | 117 | 8 | Town |
| Denning | 25 | 482 | 488 | -0.41% | 5.0 | 106 | Town |
| Hardenburgh | 26 | 218 | 223 | -0.46% | 3.0 | 81 | Town |
Wallkill is the largest city in Ulster County, with a population of 31,147.
Hardenburgh is the smallest city in Ulster County, with a population of 218.
There are 26 cities in Ulster County, New York.