6 cities
| City | County | 2026 Pop. ↓ |
|---|---|---|
| University Place | Pierce County | 35,288 |
| Union Hill-Novelty Hill | King County | 24,303 |
| Union Gap | Kittitas County | 6,596 |
| Uniontown | Whitman County | 398 |
| Union | Mason County | 200 |
| Upper Elochoman | Wahkiakum County | 71 |