| Name | What | Region | Country | Lat | Long | Elev ft. | Pop est |
|---|---|---|---|---|---|---|---|
| Soap Lake | city | Washington | United States | 47.39 | -119.49 | 1102 | |
| Sobey | city | Washington | United States | 48.07 | -122.02 | 311 | |
| Sokulk | city | Washington | United States | 47.07 | -117.21 | 2595 | |
| Somerset | city | Washington | United States | 47.57 | -122.16 | 830 | |
| Soos Creek Mobile Home Estates | city | Washington | United States | 47.36 | -122.14 | 396 | |
| Sound Vista Mobile Home Park | city | Washington | United States | 47.40 | -122.30 | 314 | |
| South Aberdeen | city | Washington | United States | 46.97 | -123.80 | 52 | |
| South Arbor | city | Washington | United States | 46.92 | -123.98 | 6 | |
| South Bay | city | Washington | United States | 47.08 | -122.85 | 127 | |
| South Beach | city | Washington | United States | 47.57 | -122.51 | 0 | |
| South Beach | city | Washington | United States | 48.98 | -123.05 | 0 | |
| South Bellingham | city | Washington | United States | 48.72 | -122.49 | 167 | |
| South Bend | city | Washington | United States | 46.66 | -123.80 | 167 | |
| South Broadway | city | Washington | United States | 46.57 | -120.52 | 997 | |
| South Cheney | city | Washington | United States | 47.47 | -117.58 | 2509 | |
| South Cle Elum | city | Washington | United States | 47.19 | -120.95 | 2034 | |
| South Colby | city | Washington | United States | 47.52 | -122.54 | 144 | |
| South Elma | city | Washington | United States | 46.98 | -123.41 | 164 | |
| South End Mobile Estates | city | Washington | United States | 48.72 | -122.49 | 180 | |
| South Highlands | city | Washington | United States | 46.19 | -119.14 | 830 | |
| South Hill | city | Washington | United States | 47.14 | -122.27 | 830 | |
| South Hill Palisade Mobile Home Park | city | Washington | United States | 47.13 | -122.29 | 830 | |
| South Montesano | city | Washington | United States | 46.96 | -123.61 | 200 | |
| South Park | city | Washington | United States | 47.53 | -122.31 | 180 | |
| South Prairie | city | Washington | United States | 47.14 | -122.10 | 830 | |
| South Seattle | city | Washington | United States | 47.56 | -122.31 | 187 | |
| South Snohomish | city | Washington | United States | 47.90 | -122.11 | 88 | |
| South Tacoma | city | Washington | United States | 47.21 | -122.48 | 298 | |
| South Union | city | Washington | United States | 46.94 | -122.91 | 200 | |
| Southern Heights | city | Washington | United States | 47.50 | -122.31 | 367 | |
| Southgate Mobile Home Park | city | Washington | United States | 47.48 | -122.28 | 252 | |
| Southworth | city | Washington | United States | 47.51 | -122.50 | 0 |